Process for the preparation of 2,2-dimethyl-3-vinyl-cyclopropanecarboxylic acids and esters

US4423243A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Manfred Jautelat · Burscheid, DE
• Dieter Arlt · Cologne, DE

Key dates

• Filing date: Dec 16, 1981
• Grant date: Dec 27, 1983
• Expiry date: Dec 16, 2001

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/00
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the production of 2,2-dimethyl-3-vinyl-cyclopropanecarboxylic acid derivative of the formula ##STR1## in which R.sup.1 is a hydrogen atom, an alkyl group or a radical of an alcohol which can be used in pyrethroids, and PA0 X.sup.1 and X.sup.2 each independently is a halogen atom PA0 or a fluorine-substituted alkyl radical, comprising adding (a) a polyhalogenoalkene of the formula ##STR2## in which X.sup.3 and X.sup.4 each independently is a halogen atom, to 1-chloro-3,3-dimethyl-pent-4-en-2-one of the formula ##STR3## in the presence of a catalyst which yields free radicals, or in the presence of a metal salt of the VIII main group or of the sub-group IVa, VIIa or Ib of the periodic system, thereby to obtain a mixture of compounds of the formula ##STR4## and (b) reacting either or both of such compounds with a base of a formula EQU (R.sup.1 --O.sup..crclbar.).sub.n M.sup.n+ PA0 in which PA0 M is an alkali metal or alkaline earth metal, and PA0 n is 1 or 2. The end products are known insecticides and intermediates therefor, while the intermediates produced by (a) are novel compounds.