Design and synthesis of 4,4′-disubstituted-[2,2′]-bipyridines for catalyzing CO/styrene copolymerization with palladium(II)

Abstract

A series of 4,4’-disubstituted-[2,2’]-bipyridines, featuring electron withdrawing/donating functional groups such as amino, chloro, nitro, ethoxycarbonyl, carboxy, methyl, methoxy and hydroxymethyl, have been synthesized and employed in the copolymerization of carbon monoxide(CO)and styrene. The available bipyridine and its derivatives were coordinated with palladium(II)acetate for catalyzing the copolymerization of CO and styrene, and the concomitant polyketone was characterized by means of ¹³C NMR, FTIR, differential scanning calorimetry( DSC)and element analysis techniques concerning its structure and thermal performance. The effect of different electron-donating and electron-withdrawing groups on catalyst performance and molecular weight of copolymer was studied under certain experimental condition. It has been proved that the enhancement of electron donating and conjugative effects on bipyridine ligand will not only improve the catalytic activity of the composition, but also increase the molecular weight of the as-prepared polyketone. The catalytic activity is the highest in hydroxymethyl substituted 2,2’-bipyridine ligand(1 356 gSTCO/(gPd · h)), when the molecular weight and polydispersity index of the polyketone are M _n=8 502,M _w=1 3440 and M _w/M _n=1.581, respectively.

Keywords

bipyridine / CO/styrene copolymerization / palladium(II)complex / polyketone

References

[1] Brubaker M M, Coffman D D, Hoehn H H. Synthesis and characterization of ethylene-carbon monoxide copolymers, a new class of polyketones [J]. Journal of the American Chemical Society, 1952, 74(6): 1509-1515.

[2] Tian J, Guo J, Zhu C, et al. Synthesis of poly(1-oxo-2-phenyltrimethylene)catalyzed by palladiumrare earth catalyst [J]. Fibers and Polymers, 2007, 8(6): 586-590.

[3] Drent E, Budzelaar P H M. Palladium-catalyzed alternating copolymerization of alkenes and carbon monoxide [J]. Chemical Reviews, 1996, 96(2): 663-682.

[4] Kosaka N, Hiyama T, Nozaki K. Baeyer-Villiger oxidation of an optically active 1,4-polyketone [J]. Macromolecules, 2004, 37(12): 4484-4487.

[5] Morita T, Okada S. Method for Producing Polyketone Fiber: JP, 2005105471(A)[P]. 2005-04-21.

[6] Barsacchi M, Consiglio G, Medici L, et al. Syndiotactic poly(1-oxo-2-phenyltrimethylene): On the mode of the chain growth under palladium catalysis [J]. Angewandte Chemie International Edition in English, 1991, 30(8): 989-991.

[7] Bianchini C, Lee H M, Barbaro P, et al. Copolymerization of carbon monoxide with ethene catalyzed by bis-chelated palladium(II)complexes containing diphosphine and dinitrogen ligands [J]. New Journal of Chemistry, 1999, 23(9): 929-938.

[8] Lyubimova O O, Baranovskii V I. Theoretical study of electron density delocalization in the excited states of transition metal complexes [J]. Journal of Structural Chemistry, 2003, 44(5): 728-735.

[9] Wang H, Guo J, Hu Guang. Ionic liquidcomplex Pd/C system as catalyst for copolymerization of CO and styrene[J]. Transactions of Tianjin University, 2014, 20(1): 48-53.

[10] Donnici C L, Maximo D H, Moreira L L C. Synthesis of the novel 4,4′-and 6,6′-dihydroxamic 2,2′-bipyridines and improved routes to 4,4′-and 6,6′-substituted 2,2′-bipyridines and mono-N-opxide-2,2′-bipyridine [J]. Journal of the Brazilian Chemical Society, 1998, 9(5): 455-460.

[11] Gillaizeau-Gauthier I, Odobel F, Alebbi M. Phosphonatebased bipyridine dyes for stable photovoltaic devices [J]. Inorganic Chemistry, 2001, 40(23): 6073-6079.

[12] Simpsox P G, Vinciguerra A, Quagliano J V. The donor properties of 2,2′-bipyridine N,N′-dioxide [J]. Inorganic Chemistry, 1962, 2: 282-286.

[13] Kavanagh P, Leech D. Improved synthesis of 4,4′-diamino-2,2′-bipyridine from 4,4′-dinitro-2,2′-bipyridine-N,N′-dioxide[J]. Tetrahedron Letters, 2004, 45(1): 121-123.

[14] Gerhard M, Francis H C. The synthesis of some 4,4′-disubstituted-2,2′-bipyridines [J]. Journal of the American Chemical Society, 1958, 80(11): 2745-2748.

[15] Jin R, Hua Youqing. Polymeric Physics [M], 2007, Beijing: Chemical Industry Press.

[16] Luo Q, Shen Mengchang. Coordination Chemistry [M], 1987, Nanjing: Jiangsu Science and Technology Press.

[17] Mul W P, van der Made A W, Smaardijk A A. Catalytic Synthesis of Alkene-Carbon Monoxide Copolymers and Cooligomers [M], 2003, Dordrecht: Kluwer Academic Publishers.

[18] Guo J, Hu G, Gao Shan. Synthesis of novel ionic liquid([C4CNmim]+PF-6)and application to preparation of polyketone[J]. Transactions of Tianjin University, 2011, 17(2): 107-110.

[19] Guo J, Xiao M, Wang Haixia. Synthesis of polyketone by copolymerization of styrene and CO using carbon nanotube-complex Pd2+ catalyst[J]. Transactions of Tianjin University, 2014, 20(2): 86-90.

[20] Guo J, Liu B, Li L, et al. Copolymerization of carbon monoxide and styrene catalyzed by palladium-rare earth catalyst[J]. Chinese Journal of Catalysis, 2004, 25(3): 231-237.