The kinetics and mechanism of the reaction between 1-chloro-2,3-epoxypropane and p-cresol in the presence of basic catalysts

Rate constants for the reaction of 1-chloro-2,3-epoxypropane with p-cresol in the presence of basic catalysts were studied at the temperature range of 71–100°C. It was found that in the presence of sodium p-cresolate, three consecutive reactions proceeded giving the following products: 1-chloro-3-(tolyloxy)-2-propanol (CTP), 1-(p-tolyloxy)-2,3-epoxypropane (TEP) as a main product, and 1,3-di(p-tolyloxy)-2-propanol (DTP). Their rate constants at 71°C were: k₁ = 0.030 ± 0.009, k₂ = 1.58 ± 0.02, and k₃ = 0.033 ± 0.005 dm³/mol · min, respectively. In the presence of quaternary ammonium salts, this process consisted of 5 reactions which led to CTP as a main product as well as TEP and 1,3-dichloro-2-propanol (DCP). The rate constant of CTP formation at 71°C was established, k₁ = 0.130 ± 0.030 dm³/mol · min, as were the ratios of the other rate constants k₂/k_?4 = 1.5 ± 0.2, k₅/k_?4 = 20.0 ± 5.0, and k₄/k₁ = 0.6 ± 0.7. Based on the changes in Cl^? ion concentration during the reaction, the catalystic activity of quaternary ammonium salts was explained. The kinetic model of these reactions in the presence of basic catalysts has been proposed and appropriate kinetic equations have been presented. © 1997 John Wiley & Sons, Inc. Int J Chem Kinet 29: 73–79, 1997.