Vapor phase hydrolysis of organic chlorides into carboxylic acid over solid acid catalysts: Part 1: Catalyst screening test for hydrolysis of vinylidene-type dichloride

Abstract

For the vapor phase hydrolysis of a vinylidene-type dichloride into its corresponding carboxylic acid, several efficient catalysts were found. They are acidic mixed metal oxides: WO 3–TiO 2, WO 3–ZrO 2, and Nb 2O 5–TiO 2. 1,1-Dichloro-3,3-dimethyl-1-butene (DDB) was effectively hydrolyzed over WO 3(1)–TiO 2(4) catalyst into 2,2-dimethylbutyric acid (DMBS), a key starting compound for a herbicide, as follows: conversion of DDB, 41%; selectivity to DMBS, 96.3%. The catalytic activity was proportional to the amount of Brønsted acidity with acid strength stronger than H 0 ≤− 3.0.