Chemical Engineering Science, Vol.61, No.18, 6199-6212, 2006
A theoretical study of solvent effects on Kolbe-Schmitt reaction kinetics
A theoretical DFT study was employed to confirm the Kolbe-Schmitt reaction mechanism and investigate solvent effects on this reaction. The use of a solvent in the Kolbe-Schmitt reaction is desirable to facilitate a homogeneous reaction mixture and potentially improve the reaction rate. The candidate solvents were designed using computer aided molecular design (CAMD) and tested using DFT solvation calculations. The results from the quantum mechanical calculations were then used to determine the rate constants for each elementary step, the overall reaction yields and the corresponding residence time. The methodology was tested on the reaction without solvent, with solvents reported in the literature, and with the designed solvents. The study revealed that in the presence of solvents with high dielectric constant the reaction becomes reversible, leading to low product yields. (c) 2006 Elsevier Ltd. All rights reserved.
Keywords:Kolbe-Schmitt reaction;density functional theory;rate constant;conventional transition state theory;computer aided molecular design;solvent design