Sustainable functionalization and modification of materials via multicomponent reactions in water

Abstract

In materials chemistry, green chemistry has established firm ground providing essential design criteria to develop advanced tools for efficient functionalization and modification of materials. Particularly, the combination of multicomponent reactions in water and aqueous media with materials chemistry unlocks a new sustainable way for constructing multi-functionalized structures with unique features, playing significant roles in the plethora of applications. Multicomponent reactions have received significant consideration from the community of material chemistry because of their great efficiency, simple operations, intrinsic molecular diversity, and an atom and a pot economy. Also, by rational design of multicomponent reactions in water and aqueous media, the performance of some multicomponent reactions could be enhanced by the contributing “natural” form of water-soluble materials, the exclusive solvating features of water, and simple separating and recovering materials. To date, there is no exclusive review to report the sustainable functionalization and modification of materials in water. This critical review highlights the utility of various kinds of multicomponent reactions in water and aqueous media as green methods for functionalization and modification of siliceous, magnetic, and carbonaceous materials, oligosaccharides, polysaccharides, peptides, proteins, and synthetic polymers. The detailed discussion of synthetic procedures, properties, and related applicability of each functionalized/modified material is fully deliberated in this review.

Key words： materials; multicomponent reactions; modification; functionalization; water

1 Introduction

Most important progress, novel innovations, and neoteric revolutions have been attained via the development of interdisciplinary sciences. These sciences make something innovative by addressing the possible limitations and accelerating the simultaneous employment and integration of the property of different sciences [1]. In this context, the combination of chemical transformations with materials science is one of the emergent interdisciplinary sciences for the preparation of custom-made materials. This can be achieved by diverse approaches for altering the origin features of the materials, for instance, biocompatibility, surface energy, surface charge, hydrophilicity, roughness, and reactivity [2–4]. On the other hand, the material functionalization or modification is the manner to amend materials over chemical or physical treatment, introducing functional groups that later can participate in the additional organic reactions or improve the chemical properties [5–8].

Typically, the conventional multistep strategy for the preparation of a multi-functionalized or modified material includes several synthetic processes, as well as extraction and purification methods in each distinct step. This causes synthetic inadequacy and makes large amounts of waste. Recent researchers showed that multicomponent reactions (MCRs) have increasingly become important in material sciences [9–12]. MCRs are suitable strategies for the convenient generation of tailor-made chemical libraries on materials with high levels of functional complexity and diversity, thereby enabling them applicable in different fields. In synthetic processes and pathways, there has been recently attracting interest in the maintenance of ‘greenness’ [ 13]. There is an importance on the employment of ‘greener’ reaction circumstances since green chemistry greatly affects chemical researches [14]. In green chemistry, solvents are the most important concern of research due to the greatest waste proportion and also their major hazard contributors and energy intensity on a typical manufacturing procedure of chemistry [15,16]. A significant aspect of green chemistry refers to the removal of hazardous organic solvents or their replacement with inexpensive, non-toxic, non-volatile, and non-flammable solvents [17,18]. In addition, the progress of alternative solvent-free methods is an appropriate choice, in which either one of the substrates or the products is in the liquid state to be acted as the reaction solvent [19,20]. On the contrary, if the solvents are essential to a progression, we should choose a greener solvent. The selection of solvent is frequently important in MCRs chemistry, since it may noticeably impact the process, selectivity, and rate of the reaction.

Fortunately, the versatility of MCRs enables researchers to select a green contributor solution in these regards. In 2009, Kumaravel and Vasuki [21] reviewed MCRs that have been carried out in water or aqueous solutions as reaction medium. In 2012, the attempts of the scientific community to the employment of MCRs in unconventional solvents have been expansively reviewed [17]. In another 2012 review article, the progress of MCRs’ chemistry in water is well represented [22]. The MCRs as advanced tools for sustainable organic synthesis were also established in 2014 [23]. In addition, the MCR strategy as an advanced tool for the functionalization or modification of materials has recently become a topic of some interesting reviews [9,10,24–30]. However, a review article that focused comprehensively on the sustainable aspect of the materials modification or functionalization using MCRs in water is not reported in the literature. So, screening this young field will open a new vision for researchers and will accelerate the development of greener strategies in materials science and as well as their applications. Hence, the aim of this review article is highlighting the most significant capacities and applications of MCRs in the design and construction of innovative materials with improved chemical properties. To end this, MCRs are briefly introduced in the following section, then exclusive aspects of MCRs in water and aqueous media are represented and finally, their recent advances in the design of modified and functionalized materials are fully presented in detail.

2 Multicomponent reactions

MCRs as advanced synthetic methods provide highly significant frameworks through a minimal number of synthetic steps. These reactions consist of at least three substrates to produce a single product that in effect all their atoms join through covalent bonds (Fig.1). Since MCRs give higher overall chemical yields compared to multiple-step syntheses, they save the use of manpower, effort, chemicals, energy, and time. Outstanding benefits like facile automation, operational simplicity, convergence, reduction in the number of workups, purification, and extraction processes, and thus minimize waste production, translate MCRs as green contributions [31–33]. On the other hand, these reactions showed greener advantages than stepwise or individual reactions such as E-factor and mass intensity as important green chemistry aspects [23,34].

Fig.1 The conventional multistep synthesis compared to the one-pot MCR method.

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Several interesting books and reviews have reported the development of MCRs as an advanced synthetic method [10,35–43]. Because of the excellent adaptable products of MCRs [23,44], they have been commonly utilized in many starting points of chemistry particularly in drug discovery and synthesis of peptidomimetics, natural products, and macrocyclic compounds [35,45–47]. Many fundamental MCRs called as name reactions, for example, Strecker [48,49], Biginelli [50,51], Mannich [52–54], Passerini [55,56], Ugi [57–59], Döbner [24], Kabachnik-Fields [60,61], and Hantzsch [62,63]. Generally, MCRs can be organized into two general classes as isocyanide- and non-isocyanide-based reactions. In general, in both types of MCRs is present an activated carbonyl substrate. They received a great consideration as a key reaction in many organic transformations [58]. On the other hand, the flexibility of the MCRs via easily available starting materials are facilely made of various types of functional moieties; moreover, their participation with other transformations has achieved miscellaneous chemical scaffolds [64–66]. In this regard, the research field of MCRs over the past two decades has received fantastic progress with the discovery of innovative strategies for green chemistry merits.

Several exclusive book chapters and reviews are today already presented on the chemistry of water since it is a hot issue in several academic workshops, with new and emerging applications in different fields [67–78]. Typically, utilizing water as the solvent of organic reactions was mostly limited to the typical hydrolysis reactions. Therefore, most catalysts and reagents of organic transformation have been frequently developed for use in anhydrous organic media, i.e., methylene chloride, toluene, or tetrahydrofuran. Now, why must we spend our time to discover reactions in water and aqueous media which work suitably in organic solvents? Since there are numerous possible benefits of changing these solvents with water. The most noticeable are the cost (there is not any cheaper than water!), safety (most organic solvents in comparison with water have risks such as flammability, explosivity, and carcinogenicity, etc.), and environmental worries (the chemical manufacturing is the main reason of environmental pollutions). The elaboration of nonhazardous replacement solvents like water or aqueous media is of great significance from organic/material chemistry viewpoint due to the remarkable features that we discuss in detail here. First, a ‘natural’ form of water-soluble materials can participate in the reaction without the requirement of hydrophobic derivatization or further protection-deprotection steps. Second, experimental methods may be simplified because separation of products and recovering water-soluble reagents and catalysts can be attained through simple phase separation. Third, the exclusive solvating features of water have positive effects on a variety of MCRs in terms of the facility for materials functionalization or modification, which will be thoroughly considered in this review.

Most important MCRs in material chemistry are shown negative activation volumes since the combination of several compounds into a single product [17]. On the other hand, promotion of the MCRs at high pressure affords additional support for this opinion [79]. This contribution makes a reaction acceleration in water especially for nonpolar reactants [80], which has been related to several reasons, i.e., the hydrophobic effect [79] and high cohesive energy density of water (cal. 550.2 mL⁻¹ at 25 °C) [20,81]. Also, the mixture solvents of organic and aqueous media have been employed in MCRs, but they are not showing the same rate of impacts as pure water as a reaction solvent. Still, this subject may contain very important issues for green chemistry merits. The operation of MCRs in pure water can offer an ideal synthetic reaction media as it combines the synthetic efficiency of multicomponent procedures with the environmentally friendly advantages of water as the reaction solvent (Fig.2). Interestingly, many exclusive MCRs have been recently developed that cannot be carried out in typical organic solvents [79]. In this area, Kumaravel and Vasuki [21], in 2009, reported an inclusive review to summarize all the early results. The following section rely on the benefits of MCRs in water and aqueous media for materials chemistry that is the focus of this review.

Fig.2 MCRs in water and aqueous media as a sustainable tool for functionalization and modification of materials.

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3 Sustainable functionalization and modification of materials

Although the materials functionalization and modification date back more than a century, still looking at this “old” materials chemistry from new viewpoints brings innovative developments in this hot research field. Recently, the multicomponent approach as a sustainable tool has remarkably enriched the materials chemistry and received great attention in materials functionalization and modification. Most materials have the potential to be contributed in MCRs as the main components such as carboxylic, amine, or carbonyl groups that are commonly existing in their structures or simply be generated on their surfaces. An important demand in this area is the ability to perform functionalized/modified materials through a sustainable method that is potentially achieved by MCRs in water and aqueous media.

The main reason that the MCRs in water and aqueous media are great approaches for materials chemistry, is their “power of sustainable”, which is the goal of green chemistry [82]. This power makes many benefits in the schemes of materials functionalization and modification [83,84], in which three major ones are emphasized. First, simple operational; this method is a straightforward one-pot procedure that does not require isolation or purification of any intermediates. Second, substrates diversity; a variety of substrates and materials can be employed in this protocol. Third, atom, pot, and step economic; this caused a significant decrease in the number of materials functionalization and modification steps. Fourth, environmentally friendly; performing this protocol in water and aqueous media significantly avoids environmental pollution and the risk of using a flammable, explosive, and carcinogenic organic solvent. Subsequently, all of these benefits make possible features of green chemistry; reduced cost, waste, and environmental worries [83].

The interesting journey of materials functionalization and modification with MCRs strategy in water and aqueous media has been started since the 1970s when Axen, Vretblad, and coworkers used isocyanide-based Ugi four-component reaction (Ugi-4CR) to immobilize biologically active materials to a variety of isocyanide substituted natural polymers [85,86]. In the following years, this approach was established for immobilizing enzymes on the different polymeric surfaces, for instance, polysaccharides, polyamides, polyester, and polyacrylamide [87]. There are few amounts in this field from that time until the 20th century. The state-of-the-art of material chemistry through the sustainable MCRs has been introduced at the beginning of the 20th century and interesting studies are related to 2010 until recently. This part of the present review will focus on the results reported regarding MCRs in water and aqueous media for modification or functionalization of materials, concerning the materials type, MCRs, reaction conditions and brief detail on their applications (Tab.1).

Tab.1 Comparison of the sustainable functionalization and modification of materials via MCRs in water

Material	Type of MCR	Reaction condition	Significant feature and application	Ref.
Graphene	Ugi-4CR	Water (pH 7.0), about 2 h, room temperature (r.t.) to 25 °C	Biocatalyst, gene delivery system, proliferation of human mesenchymal stem cells	[88–91]
Multiwall carbon nanotubes (MWCNTs)	Ugi-4CR	Water, about 1–30 min, r.t.	Biocatalyst	[89]
Oligosaccharide	A3-coupling reaction	Water, [Au(C^N)Cl2] complex, 40 °C	Bioactive compounds, appropriate for further orthogonal transformation	[92,93]
Cellulose	Passerini three-component reaction (P-3CR)	Water	Hydrogels	[94–96]
Carboxymethyl ethers of cellulose, xylan, and pullulan	P-3CR	Acidic aqueous medium, r.t., 20 h	Soluble in water and organic solvents	[97]
Filter paper, cotton linter, wood cellulose	Ugi-4CR	Water, pH 6–6.5	Cross-linked submicron microgels	[98]
Carboxymethyl cellulose (CMC)	P-3CR, Ugi-4CR	Water or phosphate buffer saline (PBS, pH 7.4), r.t.	Introducing reactive functions, antibacterial glycoconjugate vaccines motivating hydrophobicity	[99,100]
2,2,6,6-Tertramethyl-1-piperidinyloxy (TEMPO)-oxidized cellulose	P-3CR	Water, r.t.	Temperature-responsive polymers	[101]
Periodate-oxidized cellulose	P-3CR	Water, r.t.	Functionalized cellulose, used in aza-Michael reaction	[79,102]
Cotton fabric	Hantzsch-4CR	Water, r.t., 10 min	Great fluorescent materials at 460 nm	[103]
Alginate	Ugi-4CR	Water or buffered aqueous solution (pH 5), r.t.	Gel, exploring rheological performance, structural, and turbidity features, hydrophobically modifying, self-aggregated semispherical shape micelles, enzyme immobilizing, electroanalytical biosensor	[104–110]
Pectin	Ugi-4CR	Semi-dilute solutions or water, r.t. about 3 h	Gel, polyampholyte microgels	[111,112]
Hyaluronan	Ugi-4CR	Water (pH 4.0), r.t., 24 h	Hydrogel, good swelling and physical properties	[113,114]
Chitosan	Michael’s reaction	Water, 60 °C	Dithiocarbamate functionalization, lead, cadmium, and copper removal	[115]
Glucan	3-CRs (boronic ester and Schiff base formations)	Tetrahydrofuran, water, r.t.	Strong luminescence intensity, high water dispersibility, respond to pH and glucose	[116]
Bacterial capsular polysaccharides (CPs)	Ugi-4CR	PBS (pH 7.4), r.t.	Great antigenicity and extracted goods titer of functional specific antibodies	[117]
Peptide	A3 coupling, A3-macrocyclization	Semi-neat aqueous conditions or water, r.t. or 35 °C	Appropriate compounds for orthogonal modifications, azacyclopeptide CD36 modulators, peptide-based drug development	[118–120]
Protein	Mannich-type MCR, A3 coupling	PBS (pH 6.5 or 7.8), r.t. to 37 °C, using Cu catalyst	Site-selective protein labeling	[121,122]
Wool and keratin	Ugi-4CR	Water (pH 6.5), r.t.	Biocatalyst	[86]
Gelatin	3-CR	Water, r.t.	5-Aminopyrazol conjugation, hydrogel, 5-fluorouracil delivery system for rectal administration	[123]
Poly(2-dimethylaminoethyl methacrylate (PDMAEMA)	P-3CR	Water, r.t., 24 h	Monomer for reversible addition-fragmentation chain-transfer (RAFT) polymerization, endosomal escape polymers	[124]
Glycideyl methacrylate polymer, poly(ethylene terephthalate)	P-3CR, Ugi-4CR	Water or PBS, r.t.	Glucose oxidase and urease enzymes immobilizations, horseradish peroxidase (HRP) and bovine serum albumin conjugation	[123–127]
Poly-(N-isopropylacrylamide)-co-polystyrene (pNIPAm-co-pSTY)	Three-component thiolactones ring-opening reaction	Buffered solution (pH 8.0), 4 °C	Rod/worm polymeric micelles	[128]
Poly 2-(acetoacetoxy)ethyl methacrylate-co-poly (ethylene glycol methyl ether) methacrylate (PAEMA-co-PEGMA)	Hantzsch-4CR	Water, 37 °C	Formaldehyde detection in aqueous media in living systems	[129]
SiO2 nanoparticles (NPs)	Ugi-4CR	Water, r.t.	Alginate derivative conjugation, improving surface activity and cytocompatibility	[130]
Mesoporous silica nanoparticles (SBA-15)	Ugi-4CR	Water (pH 7), 25 °C	Enzyme immobilization, i.e., Rhizomucor miehei lipase (RML), biocatalyst, kinetic resolution	[131,132]
Epoxy-functionalized silica	P-3CR	Water (pH 7), r.t.	Laccase enzyme immobilization, removal of textile dyes	[133]
Amin-functionalized Fe3O4@SiO2	Ugi-4CR	Carbonate buffered solution (pH 9):EtOH, 50 °C, 12 h	Tann conjugation, core-shell magnetic NPs, doxorubicin and methotrexate delivery, higher cytotoxicity toward MCF7 cells	[134]
Aldehyde-functionalized Fe3O4@SiO2	Ugi-4CR	Water (pH 6–7), r.t., 1.5–12 h	RML and Thermomyces lanuginosa (TLL) immobilizations, biocatalysts, waste cooking oil transesterification	[135]

3.1 Carbonaceous materials

Graphene and carbon nanotubes as carbonaceous nanomaterials are going to develop in the 21st century since their many potential applications stem from their outstanding optical, mechanical, and electronic features [136,137]. Despite this importance, it has two major drawbacks: toxicity and low dispersity. The recent motivation of researchers has shown that the progress of MCRs as an innovative strategy for either modification or functionalization in water medium could efficiently overcome these problems [9,10,138,139]. In this regard, Rezaei et al. [88], in 2016, used the Ugi-4CR approach to covalently functionalize graphene 4 with different groups in water, generating the amphiphilic, hydrophilic, or hydrophobic multi-functionalized graphene composites 5 in mild circumstances (). They also utilized Bacillus thermocatenulatus lipase as an amine moiety and participated in Ugi-4CR to covalently immobilize on the surface of graphene. The immobilized lipase showed high biocatalytic activity for the hydrolysis of short- and long-chain triacylglycerols.

Scheme1 Ugi-functionalized method to prepare hydrophobic, hydrophilic, and amphiphilic multi-functionalized graphene. Reprinted with permission from Ref. [88], copyright 2016, American Chemical Society.

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Enzymes as green biological catalysts showed some superior features such as high chemo-, stereo-, and regio-selectivity [140,141]. Nevertheless, they exhibited some disadvantages in their pure forms, for example, denaturation, contamination in products, low stability in reaction conditions, and problems in reuse and recovery [142]. In this regard, Rezaei et al. [90] utilized this efficient strategy for the synthesis of a nonviral graphene-based gene delivery system 7 for high efficient plasmid DNA (pDNA) transfection into mammalian cells. In this process, ethidium bromide 3c as a fluorescent dye for detecting nucleic acids was employed to complex with carboxylated-graphene (GO-COOH) 4 under extremely mild conditions (25 °C, water), . Obtained results exhibited that prepared nanocarrier 6a in comparison with pure GO-COOH 4 has excellent biocompatibility, good stability in physiological media, and high DNA-loading capacity. Similarly, Adibi-Motlagh et al. [91], in 2017, described the straightforward Ugi-4CR strategy for the surface immobilization of the cell-adhesion peptide 3d onto the graphene (). The peptide-functionalized graphene 6b showed excellent biocompatibility and also accelerated the proliferation of human mesenchymal stem cells at a good rate concerning the tissue plate.

Scheme2 Functionalization of GO-COOH sheets through Ugi multicomponent assembly process to prepare amphiphilic graphene-EtBr. Reprinted with permission from Ref. [90], copyright 2016, American Chemical Society. And peptide-functionalized graphene. Reprinted with permission from Ref. [91], copyright 2018, Elsevier.

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In another example, RML enzyme 8 was immobilized on the surface of the MWCNTs 7 and GO-COOH 4 through an efficient Ugi-4CR in enzyme-friendly conditions; in water, at room temperature, and a short reaction time of about 1–30 min () [89]. This method improved the survival rate of common unstable proteins without a considerable diminish in the specific activity of the enzyme. Moreover, the 680 mg loading capacity of the enzyme through this protocol is comparable with previously reported methods [143].

Scheme3 One-pot Ugi-4CR for the immobilization of RML enzyme on MWCNTs. Reprinted with permission from Ref. [89], copyright 2016, Royal Society of Chemistry.

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3.2 Oligosaccharides

The development of new methods for the selective modification of biomolecules is of great interest to chemists and biologists [144]. Remarkably, since the oligosaccharides play key roles in many biological processes, such as cancer cell metastasis, host-pathogen interaction, and cell signaling, their selective functionalization or modification is high importance [145–147]. In this regard, Kung, Abbiati and co-workers [92,93] used the A³-coupling strategy in water for the selective modification of aldehyde-containing oligosaccharides 11. For this reaction, the [Au(C^N)Cl₂] complex (HC^N = 2-benzylpyridine) 14 was successfully applied as a catalyst (10 mol%) at 40 °C with good to excellent reaction yields. This approach could generate amines properly and alkynes moieties with specific groups, i.e., biotin, dansyl, or m/p-ethynylbenzene, which is appropriate for further orthogonal transformation like [3 + 2] cycloadditions ().

Scheme4 A³-coupling for the selective modification of aldehyde-containing oligosaccharides. Reprinted with permission from Ref. [92], copyright 2021, Royal Society of Chemistry, and [93], copyright 2014, Beilstein-Institut.

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3.3 Polysaccharides

In the realms of “green chemistry”, polymeric carbohydrate (polysaccharides) have been interestingly investigated as a potent platform [91]. The ability to cross-link and modify polysaccharides through MCRs protocol introduce the desired characteristics on these biopolymers, receiving great consideration in different fields, such as, prosthetic materials [148], catalysts [149,150], drug delivery [151,152], emulsifiers [153], and contact lenses [154].

3.3.1 Cellulose

In 1991, the pioneering study on the MCRs-crosslinking biopolymers was reported by König and Ugi [104]. In continues, de Nooy et al. [94–96] applied this strategy to several polysaccharides like CMC and carboxymethyl scleroglucan for constructing polysaccharides hydrogels in water and studying their structural characterization. Hydrogels synthesized using the P-3CR were transparent, but the transparency of the Ugi-produced hydrogels is attributed to the cross-linker, the polysaccharide, and the degree of crosslinking. In 2018, a similar method was employed for the functionalization of the carboxymethyl ethers of cellulose 16a, xylan 16b, and pullulan 16c [97]. The reactions were performed using propargylamine 3e and 2-methoxyethylamine 3d, benzaldehyde 2e and paraformaldehyde 2d, and also tert-butyl isocyanide 1b in acidic aqueous medium at room temperature over 20 h (). The results confirmed that the Ugi-functionalized polysaccharide 17 was soluble in water and also organic solvents, such as dimethylformamide, dimethylacetamide, and dimethyl sulfoxide.

Scheme5 Ugi-4CR of carboxymethylated polysaccharides with different aldehydes, amines, and tert-butyl isocyanide. Reprinted with permission from Ref. [97], copyright 2018, Springer.

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Interestingly, Shulepov et al. [98], in 2016, used the Ugi-4CR for the construction of cross-linked submicron microgels from a variety of pure cellulose including filter paper, cotton linter, wood cellulose, and Avicel to be employed as potential Pickering emulsifier. Cellulose 16a was firstly carboxymethylated via the sol−gel transition in NaOH/urea solutions followed by the addition of sodium monochloroacetate agent18. Then, 1,4-bis(3-isocyanopropyl)piperazine 1c as a crosslinking agent and a different type of amines 3 were added to produce cross-linked submicron microgels 19 (). The authors cannot synthesize desired cross-linked microgels from filter paper and cotton linter because of their higher molecular weight.

Scheme6 The Ugi-4CR for the construction of cross-linked cellulose submicron microgels. Reprinted with permission from Ref. [98], copyright 2016, Springer.

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Another work, in 2019, described the chemical modification of CMC 20 via the P-3CR in an eco-friendly and straightforward method (aqueous medium, mild reaction conditions, one-pot, absence of catalysts or coupling agents), [99]. Remarkably, the achieved derivatives 21 maintain their solubility in water when an appropriate modification extent is targeted product in an aqueous medium by P-3CR. The benefits of this protocol for the modification of CMC were further extended with the ability of the modified CMC to physically bind into cellulosic surfaces. Results revealed that the playing on the nature of the used isocyanide 1 and aldehyde 2 reagents can tolerate the suitably modifying the surface chemistry of cellulosic substrates (e.g., introducing reactive functions) and/or their surface properties (e.g., acting on their hydrophobicity).

Scheme7 The P-3CR between CMC and different isocyanides and aldehydes. Reprinted with permission from Ref. [99], copyright 2019, American Chemical Society.

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Similarly, Khine et al. [101] benefited from the advantages of P-3CR efficiently modified the surface of TEMPO-oxidized cellulose nanofibers 22 with temperature-responsive polymers, pNIPAm, 23 under a mild condition in water. In this study, a pNIPAm with aldehyde functionality (pNIPAm-COH) 24 obtained by RAFT polymerization procedure, a cellulose nanofiber with carboxylic acid moieties 22, and cyclohexyl isocyanide 1a, were reacted in aqueous conditions at ambient temperature (). The chemical coupling with 36% of grafting efficiency was proved by improved aqueous dispersibility. Similarly, García et al. [100] successfully employed the Ugi-4CR strategy for the construction of thermostable neoglyconenzymes conjugating trypsin with CMC to yield polysaccharide-trypsin glycoconjugates.

Scheme8 The preparation of temperature-responsive polymer-graphited cellulose nanofibers via P-3CR. Reprinted with permission from Ref. [101], copyright 2018, American Chemical Society.

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In all the aforementioned examples, cellulose substrate participated as the carboxylic acid component in MCRs. These protocols prevent the employment of several important renewable carboxylic acid components for the modification of cellulose. In this regard, to extend the scope of cellulose-based biomaterials, Esen and Meier [102], in 2020, described an efficient and sustainable alternative route to functionalize cellulose. In a straightforward method, cellulose 16a was firstly oxidized to 2,3-dialdehyde cellulose 25 using sodium periodate (NaIO₄) in an aqueous medium. Then, it was modified through the P-3CR using commercially obtainable isocyanides 1 and several renewable carboxylic acids 26 (), obtaining a degree of substitution in the range of 0.62 and 0.94. This reaction was performed in an aqueous medium since the solubility of 2,3-dialdehyde cellulose in water and also acceleration of the P-3CR [79].

Scheme9 The P-3CR for the modification of dialdehyde-functionalized cellulose in an aqueous medium. Reprinted with permission from Ref. [102], copyright 2020, American Chemical Society.

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As well, Pettignano et al. [155], in 2020, modified dialdehyde-functionalized cellulose microfibrils 28 (oxidizing through the periodate oxidation technique) via the eco-friendly P-3CR in water to bear either an alkyne or a methacrylate functional group. In water at ambient temperature, the alkyne-functionalized cellulose microfibrils 31a were easily reacted through copper-catalyzed Huisgen cycloaddition with grafting two different azides while their methacrylate-functionalized form 31b were simply reacted with an amine 3e through the aza-Michael reaction (). This facility to post-modification through different common ligation reactions makes a variety of tailor-made cellulosic microfibrils in an aqueous procedure, in which their surface characteristics can be suitably perceived to the goal application. Results proved that the water media permits the higher P-3CR efficiency and functionality cellulose.

Scheme10 The P-3CR for the modification of dialdehyde-functionalized cellulose microfibrils and their post-modification through aza-Michael Huisgen reactions in an aqueous medium. Reprinted with permission from Ref. [155], copyright 2020, American Chemical Society.

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Recently, Wang et al. [103] employed Hantzsch reaction to endow fluorescent cellulosic materials. In this work, acetoacetyl-bearing cotton fabric prepared through transesterification with tert-butyl acetoacetate has participated in an aqueous Hantzsch reaction with ammonium acetate and formaldehyde at ambient temperature. Hantzsch-functionalized cotton fabric shows a strong fluorescent emission around 460 nm within 10 min. This sustainable method is talented to be generally applied to different forms of cellulosic materials and as well as various aldehyde functionalized materials.

3.3.2 Alginate

The first employment of alginate as an acid part in Ugi-4CR by Ugi [104] has opened a new avenue for the synthesis of hydrogels. They produced a novel alginate gel using Ugi-4CR to capture different enzymes such as “acidic phosphatase” and L-(+)-lactate dehydrogenase. In following up, Bu et al. [105,106] synthesized alginate hydrogels via the Ugi-4CR in aqueous solution and explored their rheological, structural, and turbidity features. Sodium alginate, 1,5-diaminopentane or n-octylamine formaldehyde, and cyclohexyl isocyanide contributed to these reactions for hydrogel construction. It was shown that the properties of the Ugi-functionalized hydrogels, such as viscoelasticity, gel point, transparency, and structure were adjusted by changing the cross-linker concentrations, the surfactant, and reaction temperature. In the same line, they described the rheology of aqueous alginate during gelation with the Ugi-4CR and effects of pH on dynamics [107]. Also, they considered the interactions between sodium dodecyl sulfate and alginate derivative that hydrophobically modified by Ugi-4CR [108]. Similar to Bu’s procedure, Yan et al. [109], in 2016, developed the same strategy for the preparation of amphiphilic Ugi-functionalized alginate and synthesized self-aggregated semispherical shape micelles with the average size of 162.3 nm using the hydrophobic interaction among the cyclohexyl and octyl groups. In another study, Camacho et al. [110] immobilized the HRP enzyme 41 on alginate modified gold electrode 40 via an efficient Ugi-4CR strategy. In this method, aldehyde moieties were introduced into the polymeric backbone of sodium alginate 37 using NaIO₄. Afterward, the cysteamine 38 was conjugated to the oxidized sodium alginate to be covered the surface of the gold electrode through a covalent S–Au bond. Finally, the Ugi-4CR was used for the immobilizing HRP enzyme 41 on the alginate coated-Au electrode 39 in enzyme-friendly media (buffered aqueous solution, pH 5), . This electrode 42 as a biosensor revealed a fast electroanalytical response with good sensitivity toward H₂O₂ even after one month of storage at 4 °C.

Scheme11 The Ugi-4CR for immobilizing HRP enzyme on alginate-modified gold electrode in buffered aqueous solution. Reprinted with permission from Ref. [110], copyright 2007, Elsevier.

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3.3.3 Pectin

In advance to environmental-friendly hydrogels, Werner et al. [111], in 2006, utilized Ugi-4CR for gelation of pectin in semi-dilute solutions. The obtained results revealed that increasing cross-linker and polymer concentrations promote faster gelation and make stronger gels. Another successful strategy for the synthesis of tailor-made polyampholyte microgels from colloidal salts of pectinic acid was applied by Mironov et al. [112] to be used as pH-responsive emulsifiers. As seen in , the formaldehyde 2a and 1,4-bis(3-isocyanopropyl)piperazine 1c were added to the aqueous colloidal suspension of pectinic acid salt 43 and benzylamine 3a for obtaining polyampholyte microgels 44, which able to protonate in acidic medium or deprotonate in basic medium. It was shown that different properties of particle size and surface were obtained by variation in amine solubility, i.e., increasing the solubility of amine result in the microgels particle diameter reduction.

Scheme12 Ugi-4CR crosslinking of pectin for the synthesis of pH-responsive emulsifier. Reprinted with permission from Ref. [112], copyright 2013, Springer.

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3.3.4 Hyaluronan

Hyaluronan or hyaluronic acid, a linear polysaccharide with anionic, nonsulfated repeats of D-glucuronic acid and N-acetyl-D-glucosamine, has been participated in Ugi-4CR by Crescenzi et al. [113]. Hyaluronan hydrogels were chemically prepared with different cross-linking degrees via the Ugi-4CR of formaldehyde, cyclohexyl isocyanide, and partially deacylated hyaluronic acid as the both primary amino and carboxylate compounds. In another work, the same group constructed a hyaluronan hydrogel 47 through Ugi-4CR of deacylated hyaluronic acid 45 and lysine 46 as a cross-linking agent with good swelling and physical properties () [114].

Scheme13 The preparation of hyaluronan hydrogel via Ugi-4CR using Lysine as a cross-linker. Reprinted with permission from Ref. [114], copyright 2003, Elsevier.

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3.3.5 Chitosan

In an attempt to develop the diversity of MCRs for material chemistry, an exclusive dithiocarbamate MCR has recently realized great opportunities for material functionalization/modification in water [115,156,157]. Khan et al. [115] utilized this three-component strategy on chitosan 48, carbon disulfide 49, and acrylamide 50 through simple Michael’s reaction in water to make dithiocarbamate derivative of chitosan 51 (). The chemically attached two pendant groups of dithiocarbamate on chitosan showed the highest sorption capacity for lead, cadmium, and copper removal from aqueous solution.

Scheme14 The dithiocarbamate-3CR for the modification of chitosan in water. Reprinted with permission from Ref. [115], copyright 2011, Elsevier.

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3.3.6 Glucan

Wan et al. [116] applied another one-pot MCRs method for the synthesizing pH and glucose-response amphiphilic aggregation-induced emission (AIE) active fluorescent organic nanoparticles (FONs) based on glucan polysaccharide, a polysaccharide of D-glucose monomers linked by glycosidic bonds. This reaction was performed through the formation of phenyl boronic ester and Schiff base reaction of 3-aminobenzeneboronic acids3f, hydrophilic glucan 52, and hydrophobic 4-(1,2,2-triphenylvinyl)benzaldehyde (TPE-CHO) AIE dye in water and tetrahydrofuran mixture solvent at room temperature about 2 h (). In aqueous solution conjugated glucan-TPE FONs 53 with amphiphilic properties self-assembled into nanoparticles. The prepared glucan-based FONs showed strong luminescence intensity and high water dispersibility, which can respond to pH and glucose because of the presence of Schiff base and phenyl borate moieties.

Scheme15 The synthetic procedure of TPE-CHO and Glucan-TPE FONs via a facile one-pot method. Reprinted with permission from Ref. [116], copyright 2016, Royal Society of Chemistry.

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3.3.7 Bacterial CPs

In the field of antibacterial glycoconjugate vaccines, for the first time, Méndez et al. [117] successfully applied Ugi-4CR in PBS (pH 7.4) for the bioconjugation of carrier proteins like diphteria and tetanus toxoids (DT & TT) to functionalize CPs, i.e., Salmonella and Streptococcus. The proteins were activated by the reaction of hydrazine with aspartic acid and glutamic side chains (DTa & TTa). The bioconjugation products exhibited great antigenicity and extracted goods titer of functional specific antibodies. Alike this method, they also conjugated two different polysaccharides to a carrier protein using periodate oxidized CPs 54 (oxo component), TEMPO-oxidized CPs 55 (carboxylic component), and TTa 56 (amino component) in the presence of tert-butyl isocyanide 1b. The Ugi-resultant glycoconjugates elicited good titers of functional specific antibodies and exhibited great antigenicity (), confirming the potential of the multicomponent bioconjugation method for the progress of multivalent vaccine.

Scheme16 Ugi-4CR for the protein-glycoconjugates of two oxo-functionalized CPs to hydrazide-activated TT. Reprinted with permission from Ref. [117], copyright 2018, Royal Society of Chemistry.

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3.4 Peptide

In particular, peptides are frequent objects of conjugation, modification or functionalization to alter their pharmacological and chemical properties for therapeutic agents’ utilization [158–160]. Uhlig and Li [118] described a highly efficient method for the direct and site-specific functionalization of amino acids and peptides, under ambient conditions through A³-coupling reaction in semi-neat aqueous conditions using copper(I) chloride as a catalyst (). Different amino acids 58 were functionalized to form dipropargylated products 59 in moderate to excellent yields. Moreover, the propargylamine moieties in products 59 offer a convenient functionality for further orthogonal modifications like “click” reaction. Also, the combination of A³-coupling and click reaction has been used for the synthesis of valuable dendritic materials [161]. On the other hand, various applicable catalysts based on the efficient materials for the A³-coupling have been introduced so far [162–167].

Scheme17 A³-coupling functionalization of amino acids and dipeptides (TMS: trimethylsilyl). Reprinted with permission from Ref. [118], copyright 2012, American Chemical Society.

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Macrocyclic peptides are attractive compounds for drug discovery [166,167]. Since their cyclic structures, they can easily stabilize active conformers and enhance the bio-selectivity and affinity [168,169]. Recently, Ong, Lubell and coworkers [119,120] successfully utilized a multicomponent “A³-macrocyclization” method for the construction of diverse cyclic azapeptides 60 in aqueous media using CuI as coupling agent (). Investigation of their structure—activity relationships has provided interesting information about constructing more potent azacyclopeptide CD36 modulators with great therapeutic potential. This explained the efficiency of A³-coupling macrocyclization as the diversity-oriented approach in peptide-based drug development.

Scheme18 Diversity-oriented A³-macrocyclization and mechanism of Cu chelation of the amine and acetylene components (n = different di-amino acid side-chain lengths, R¹, R⁴, and R⁵ = diverse carbonyl and amine substituents, –NHR³, R²CO–, and Xaa = peptide chains). Reprinted with permission from Ref. [119], copyright 2017, Wiley, and Ref. [120], copyright 2021, American Chemical Society.

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3.5 Protein

This section will focus on the protein’s functionalization/modification through MCRs in aqueous solution or PBS as protein-friendly media, but their immobilization and conjugation to different supports will be discussed in other sections of the present review. In 2004, Joshi et al. [121] applied Mannich-type MCR in PBS (pH 6.5) for the protein labeling at Tyr residues (). This reaction was carried out between Tyr phenol ring 64 and imines derived from aldehydes 2 and electron-rich anilines 3 carrying rhodamine tag to produce labeled proteins 65 ((a)). Another strategy for site-selective protein labeling 67 has been reported based on Cu-catalyzed A³-coupling reactions in PBS (pH 7.8, 0.1 mol·L⁻¹) [122], (b).

Scheme19 Site-selective protein labeling at Tyr residue by (a) Mannich type MCR. Reprinted with permission from Ref. [121], copyright 2004, American Chemical Society. (b) Cu-catalyzed A³-coupling MCR. Reprinted with permission from Ref. [122], copyright 2017, Wiley-VCH.

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In 1971, Axen et al. [86] utilized the Ugi-4CR approach for covalent fixation of chymotrypsin on the surface of fibrous structural proteins like wool and keratin. This procedure was performed by the reaction of enzyme, wool or keratin, acetaldehyde, 3-(dimethylamino)propyl isocyanide, and acetate, which was treated in distilled water at pH 6.5. Remarkably, the activity of chymotrypsin was retained after attaching to wool or keratin. In following this work, Nazeri et al. [123] designed an efficient one-pot procedure in water for the construction of 5-aminopyrazole-conjugated gelatin hydrogel 68. This reaction was performed through the chemically cross-linking of gelatin with glutaraldehyde 2i and followed by conjugation of 5-aminopyrazole 69 as a bioactive scaffold in water (). The prepared hydrogel 70 as a controlled 5-fluorouracil delivery system for rectal administration showed a fast drug release rate with notable cytotoxicity against HT29 cancer cells.

Scheme20 The synthesis of 5-aminopyrazole-conjugated gelatin hydrogel through an efficient 3-CR in water. Reprinted with permission from Ref. [123], copyright 2020, Elsevier.

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3.6 Synthetic polymers

Different types of human-made polymers have been participated in MCRs with a plethora of applications. For example, Zha et al. [124], in 2015, designed and synthesized endosomal-escape polymers from monomers by integrating imidazolyl and alkyl via P-3CR in water and following RAFT presider (). After producing the endosomal escape polymers, PDMAEMA 74, with proper degrees of polymerization, they were employed as intracellular gene delivery vectors. The pDNA-loaded polyplexes 74 exhibited great endosomal escape in comparison with blank PDMAEMA, ultimately realizing dramatically improved gene transfection efficacy.

Scheme21 The P-3CR synthetic processes for the preparation of monomers, 1-(1H-imidazol-4-yl)-2-(butylamino)-2-oxoethyl methacrylate (ImBAMA) and 1-(1H-imidazol-4-yl)-2-(octylamino)-2-oxoethyl methacrylate (ImOAMA), and RAFT method for the fabrication of block copolymers, PDMAEMA-b-PImBAMA and PDMAEMA-b-PImOAMA (AIBN: 2,2'-azobis(2-methylpropionitrile; CPADB: 4-cynopentanoic acid dithiobenzoate). Reprinted with permission from Ref. [124], copyright 2015, American Chemical Society.

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Also, several works utilized efficient Ugi-4CR procedures for protein immobilization on polymeric carriers. For example, the glucose oxidase enzyme was immobilized on aminofunctionalized glycideyl methacrylate polymer using an excess of cyclohexyl isocyanide and acetic acid to construct the “polymer-supported protein” [125]. Similarly, HRP and bovine serum albumin conjugates via Ugi reaction using either the amino or carboxylic acid groups at the biomaterial surface and isocyano components to yield divers Ugi-derived glyconjugate compounds [126]. Recently, chemically isocyanide-functionalized polyesters were participated in MCR approach to immobilize enzyme in an aqueous buffer at neutral pH by Blassberger et al. [127]. The generated functional isocyanide groups on the poly(ethylene terephthalate) 75 via P-3CR were contributed in Ugi-4CR to covalently attach the trypsin or urease enzymes 82 on the isocyanide-functionalized polyesters 80 in the presence of excess amounts of acetate 81 and acetaldehyde 2d compounds ().

Scheme22 P-3CR for the synthesis of the isocyanide derivatives of polyester and Ugi-4CR for its subsequent enzyme immobilization. Reprinted with permission from Ref. [127], copyright 1978, Wiley-VCH.

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Jia et al. [128] multi-functionalized rod/worm polymeric micelles 84 through an efficient multicomponent thiolactones ring-opening reaction in aqueous buffered solution (pH 8.0). In this work, rod/worm polymeric structures were synthesized based on diblock copolymers of pSTY and pNIPAm through the temperature-directed morphology transformation technique. Then, a one-pot three-component manner was carried out for the ring-opening of β-thiolactone-functionalized rods/worm 85 via dipyridyl disulfide 86 and allylamine 3h, generating an alkene/pyridine disulfide bifunctional rod/warm micelle 87 ().

Scheme23 Three-component thiolactone ring-opening for the modification of rod/worm micelles. Reprinted with permission from Ref. [128], copyright 2014, American Chemical Society.

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Hantzsch-4CR has been recently employed for the formaldehyde detection in aqueous media. In this interesting work, Liu et al. synthesized water-soluble polymers, PAEMA-co-PEGMA 90, to detect formaldehyde 2a in living systems via the Hantzsch-4CR () [129]. The designed polymeric fluorescent probes in comparison with common materials for formaldehyde monitoring exhibited similarly and, in some cases, albeit better sensitivity for formaldehyde monitoring. Also, this polymer 90 with great biocompatible features can efficiently be developed for endogenous formaldehyde detection in cells or zebrafish. This work reflects the efficacy of MCRs in water and aqueous media as the sustainable method in interdisciplinary fields.

Scheme24 The Hantzsch-4CR for the formaldehyde detection in living systems through polymeric fluorescent probes. Reprinted with permission from Ref. [129], copyright 2018, American Chemical Society.

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3.7 Siliceous materials

Some of the main drawbacks of SiO₂ NPs prepared by the Stöber method are their low biocompatibility, very hydrophilicity, chemically inertness, and particles aggregation in physiological media. To resolve this problem, Yan et al. [130] attempted to functionalize the surface of SiO₂ NPs 91 with amphiphilic amidic alginate derivative (AAD) 92 as the modifier via Ugi-4CR in water (). The average diameter and zeta potential of SiO₂ NPs were increased by covalent bonding of alginate derivative onto their surface; stimulatingly, this manner improved their colloidal stability in PBS. Furthermore, cell studies and surface tension determination confirmed that the AAD-SiO₂ NPs 94 was improved their surface activity and cytocompatibility.

Scheme25 The Ugi-4CR synthetic method for the surface modification of SiO₂ NPs with AAD. Reprinted with permission from Ref. [130], copyright 2020, Springer.

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Mohammadi et al. [131], in 2015, utilized the Ugi-4CR as an innovative strategy to covalently immobilize RML on aldehyde-functionalized silica supports for transesterification of methanol with colza oil to yield fatty acidic methyl esters. In this work, the first silica-gel or SBA-15 were functionalized with 3-glycidoxypropyltrimethoxysilane to generate an epoxy-functional group, and then it was oxidized using NaIO₄ solution to produce aldehyde groups on the surfaces of silica that is required to participate in Ugi-4CR. The enzyme with carboxylic acid and amino functionality simultaneously acts as a two-component part of the Ugi-4CR. The reaction was performed in water (pH 7) by the addition of isocyanide at 25 °C. The results showed that the Ugi-functionalized supports with a higher loading capacity, cosolvent, and thermal stability have a great specific activity in the presence of three polar organic solvents (dioxane, 1-propanol, and 2-propanol) in comparison with a soluble enzyme. The same group, in 2018, used amine-functionalized silica and SBA-15 for the immobilization RML by similarly applying the Ugi-4CR method in water medium to develop biocatalyst for the kinetic resolution [132]. Another group employed epoxy-functionalized silica 97 to immobilize the laccase enzyme 98 from Myceliophthora thermophile in distilled water (pH 7.0) by utilizing the P-3CR () [133], reaching a great immobilization yield (50 mg·g^–1) in a short reaction time. The immobilizing laccase enzyme 98 with the prominent activity improved the stability of enzyme to the organic solvents, pH, and temperature. The immobilized laccase 99 reveals more effective biocatalysts for the removal of textile dyes.

Scheme26 The P-3CR for the immobilizing M. thermophile laccase on epoxy-functionalized silica. Reprinted with permission from Ref. [133], copyright 2018, Elsevier.

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3.8 Magnetic NPs

Magnetic particles especially their iron oxide form have hydrophobic properties, thus no surface coatings or modifications may observe the agglomeration and aggregation in aqueous media. In this regard, Javanbakht et al. [134] developed pH-responsive double core-shell magnetic NPs as a co-delivery system via the Ugi-4CR strategy in carbonate buffer solution (pH 9), in which biologically active tannic acid (Tann) was used as modifier agent. First, Fe₃O₄ magnetic NPs were aminated by using SiO₂ shell. Then, Tann was employed in a carbonate buffered solution (pH 9) to pH-catalyzed the oxidation of the pyrogallol groups for use as a carbonyl component in the Ugi-4CR procedure. This efficient synthetic strategy was carried out among the readily available starting materials, including Fe₃O₄@Si₂O-NH₂93, p-methyl benzoic acid 26c, cyclohexyl isocyanide 1a, and Tann 100 to form peptidomimetic shell onto Fe₃O₄ NPs 101 (). According to zeta potential data, the negative zeta potential values (–13.4 mV) of the prepared double core-shell magnetic NPs were promoted to be stable in aqueous media for 20 days. In vitro doxorubicin and methotrexate delivery performance displayed a minimal drug release profile at pH 7.4, but it is significantly higher at pH 5; moreover, higher cytotoxicity was observed toward MCF7 cells in comparison with free drugs.

Scheme27 Synthesis of magnetic double core-shell nanocarrier using Ugi-4CR methodology. Reprinted with permission from Ref. [134], copyright 2020, Elsevier.

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In another work, silica core-shell magnetic NPs (Fe₃O₄@SiO₂) 102 were functionalized with aldehyde groups to be immobilized Lipase 104 from RML and TLL on their surface via the more likely Ugi-4CR approach in enzyme-friendly media, distilled water (pH 6–7), an extremely mild condition () [135]. It was shown a rapid immobilization of both enzymes in 1.5–12 h with a high loading capacity (81 and 97 mg for RML and TLL, respectively) and great immobilization yields (81%–100%). The immobilized materials105 as reusable biocatalysts were employed to generate biodiesel through waste cooking oil transesterification. Under optimal conditions, the yield of biodiesel production by immobilized TLL was calculated to be 93.1% whereas for RML it was 57.5%.

Scheme28 The Ugi-4CR for the immobilizing RLM and TLL enzymes on the surface of aldehyde-functionalized silica core-shell magnetic NPs. Reprinted with permission from Ref. [135], copyright 2020, Elsevier.

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4 Conclusions and perspectives

In the last ten years, the chemistry of MCRs has become an important strategy for materials science. The combination of MCRs with materials chemistry has introduced modern functional constructions with flexible structures, opening an innovative avenue in interdisciplinary research. MCRs were considered an effective approach to achieving a “sustainable tool” for material chemistry where the target materials were prepared in one step, in the desired yield from inexpensive and easily accessible starting materials in an effective process. They were showed greener advantages than stepwise or individual reactions such as E-factor and mass intensity as important green chemistry aspects. MCRs have received significant consideration from the community of material chemistry because of their high efficiency, intrinsic molecular diversity, and atom and pot economy with simple operation. Despite this, solvents are the most important concern of green chemistry due to the greatest waste proportion and their major hazard contributors and energy intensity on a typical chemical manufacturing procedure. Alternative media have been recently proposed as green reaction media to combat the harmful effect of organic solvents commonly used for organic transformations in large quantities. On the other hand, the challenges presented by “green chemistry” for sustainable materials functionalization and modification are addressed by MCRs in water and aqueous media. The use of these green media often triggers some simultaneous improvement in the system, which cannot be attained using other ways, even under solvent-free conditions. The performance of some MCRs could be enhanced by controlling the solubility of the starting materials in water since the reactions were performed either “in water” or “on water”. The exclusive solvating features of water have positive effects on various MCRs in terms of the facility for materials functionalization or modification, which will be thoroughly considered in this review. Moreover, the participating “natural” form of water-soluble materials along with simple separation and recovering materials make this protocol potential to emerge, set, and progress new MCRs for the next generation of multifunctional materials. Whereas significant progress has been recently made on the MCRs in water and aqueous media for organic transformations, contributing material chemistry with this sustainable field has been rarely investigated so far. On the other hand, MCRs in water and aqueous media have only recently been considered as an advanced tool for sustainable synthetic chemist’s toolboxes in the interdisciplinary fields. The research is in its beginning, and more effort should be deliberated to realize this contribution. More efforts should be devoted to these exclusive routes to fully address their possible marketable applications. To achieve an ideal tool for interdisciplinary sciences, we believe that the current review by illustrating a new avenue will encourage researchers to organize many interesting innovations in material chemistry, accelerating the development of other multifunctional materials for different applications. No doubt, this green contribution bridges the gap between the interdisciplinary sciences.

Acknowledgements

This paper has been supported by the Research Council of Shahid Beheshti University and the RUDN University Strategic Academic Leadership Program (A. Shaabani).

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