Abstract：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.
出版日期: 2008-03-05
引用本文:
. Kinetics of halogen-exchange fluorination of
2,6-dichlorobenzaldehyde[J]. Frontiers of Chemical Engineering in China - Selected Publications from Chinese Universities, 2008, 2(1): 59-62.
LIANG Zhengyong, LI Bindong, FENG Chao. Kinetics of halogen-exchange fluorination of
2,6-dichlorobenzaldehyde. Front. Chem. Sci. Eng., 2008, 2(1): 59-62.
Banks R E Mothersdale K N Tipping A E Halex fluorination of chlorinated benzaldehydes and benzoylchloridesJ Fluorine Chem 1989 44529537
2
Yoshida Y Kimura Y A convenient synthesis of fluorobenzaldehydesby KF/Ph4PBr/18-crown-6 regent systemChem lett 1988 (8)13551358
3
Liang Z Y Xu. Li B D Lv C X Synthesis of4-fluorobenzaldehyde by halogen-exchange fluorinationFine Chemicals 2005 23210513(in Chinese)
4
Yoshida Y Kimura Y An improved and practical synthesisof 4-fluorobenzaldehyde by halogen-exchange fluorination reactionJ Fluorine Chem 1989 44291298
5
Miysjims F Iijima T Tomoi M Kimura Y Aromatic nucleophilicfluorination with KF catalyzed by polymer-supported phosphonium saltsunder solid-solid-liquid phase transfer conditionsReact Funct Polym 2000 43315324
6
Xu J Z Shi Z Y Hong C H Kinetics of O-fluoronitrobenzene preparation from O-chloronitrobenzeneChemical Engineering (China) 1995 3298301(in Chinese)
