Patent · US Expired

Preparation of 3,3-dimethyl-cyclopropane-1,1,2-tricarboxylic acid derivatives and intermediates therefor

US4307033A · kind A · utility

2Cited by

3References

7Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Hellmut Hoffmann
Fritz Maurer · Wuppertal, DE
Uwe Priesnitz · Solingen, DE
Hans-Jochem Riebel · Bad Camberg, DE

Key dates

Filing date	May 27, 1980
Grant date	Dec 22, 1981
Priority date	—
Expiry date	May 27, 2000

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07C255/45
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

3,3-Dimethyl-cyclopropane-1,1,2-tricarboxylic acid derivatives of the formula ##STR1## in which R is alkyl, and PA1 R.sup.1 and R.sup.2 each is alkoxycarbonyl or cyano, with the proviso that at least one of them is cyano, suitable for use as intermediates in making insecticides, are produced by reacting a .beta.,.beta.-dimethyl-acrylic acid nitrile of the formula ##STR2## with bromine or chlorine at a temperature between about -20.degree. and +50.degree. C. to produce a compound of the formula ##STR3## in which Hal is chlorine or bromine, which compound is further reacted with a malonic acid derivative of the formula ##STR4##

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.