Under the conditions of phase transfer catalysis and nitrobenzene as the solvent, the halogen-exchange fluorination of 2,6-dichlorobenzaldehyde using KF as fluorinating agent was studied. The kinetics was investigated and the reaction rate constants were obtained under the optimum conditions of n(KF):n(2,6-dichlorobenzaldehyde):n(Ph4PBr):n(acetone-furan crown ether) = 4:1:0.1:0.05 and temperatures of 433 K, 443 K, 453 K and 463 K. The results illustrated the activation energy of the first and the second step is 4.57 × 104 J·mol-l and 3.53 × 104 J·mol-1, respectively. The pre-exponential factor is 4.50 × 105 h-1 and 1.08 × 104 h-1, respectively. Thus a reliable kinetics data could be obtained for further research.
LIANG Zhengyong, LI Bindong, FENG Chao
. Kinetics of halogen-exchange fluorination of
2,6-dichlorobenzaldehyde[J]. Frontiers of Chemical Science and Engineering, 2008
, 2(1)
: 59
-62
.
DOI: 10.1007/s11705-008-0008-1
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