Process for the preparation of 2-(4-chlorophenylethyl)-2-tert.-butyl-oxirane

US4988829A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Paul Fiedler · Cologne, DE
• Martin Littmann · Middletown, US
• Manfred Lenthe · Odenthal, DE
• Achim Noak · Cologne, DE
• Gerd Siekmann · Cologne, DE

Key dates

• Filing date: Jun 30, 1989
• Grant date: Jan 29, 1991
• Expiry date: Jun 30, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D303/08
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for making the known fungicide intermediate 2-(4-chlorophenyl ethyl)-2-tert.-butyloxirane of the formula ##STR1## comprising (a) mixing a solution of trimethylsulphonium bromide of the formula EQU (CH.sub.3).sub.3 S.sup..sym. Br.sup..crclbar. (II) PA0 in a methanol/toluene mixture with preheated toluene and simultaneously distilling off a methanol/toluene mixture at a temperature between 65.degree. and 110.degree. C. until a suspension having a solids content between 10 and 70% by weight is formed, and PA0 (b) reacting the suspension of trimethylsulphonium bromide in toluene thus obtained with 1-(4-chlorophenyl)-4,4-dimethylpentan-3-one of the formula ##STR2## in the presence of solid potassium hydroxide, diethylene glycol and water at a temperature between 20.degree. and 120.degree. C., the amounts of the reaction components being such that per mole of 1-(4-chlorophenyl)-4,4-dimethylpentan-3-one of the formula (III) there are present PA1 between 1 and 2 moles of trimethylsulphonium bromide of the formula (II), PA1 between 2 and 3 moles of solid potassium hydroxide and also PA1 between 0.1 and 10% by weight of diethylene glycol and between 0.5 and 12% by weight of water, …