Kinetic Study on Addition of Carbon Monoxide to Methallyl Chloride in Hydrogen Fluoride Medium under High Pressure

Abstract

Synthesis of B-chloropivalic acid from methallyl, , chloride (3-chlbro-2rmethyl-1-ptopene) and carbon monoxide in hydrogen Huoride m, edium was st udied kirtet/lcally. Since tarry matter formed-at increased temperature and concentration, the favorable conditi ohs are confined te the reaction temperature below OOC and the charge mole ratio of methallyl ehlbride to hydrogen fiuoride less than O, 02. FQr example, 94 mol% yield of B-chlorepivalic acid was attained in 1.5hr under the conditions carbon monoxide pressure 15Q. atm, temperature 10C, the charge mole ratio O. Ol.
Rate 6quation, derived from.. the prqpQsed mechanism of carbon monoxide addition to the carbonium ioR foitned ftom Methallyl chloride in hydrogen fluoride, can explain quantitatively the'effects bf pressure and the charge mole ratio, The rate constants (atin-1, min-1), 1.68 10S (-10eC), 5.03 10-4 (-200C)i 2.02 10w (30eC), and the apparent a6tivation energy, 14kca1, mol1, have been obtained.