Patent · US Expired

Preparation of cyclopropanecarboxylic acid esters

US4299972A · kind A · utility

1Cited by
3References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 1, 1980
Grant dateNov 10, 1981
Priority date
Expiry dateJul 1, 2000

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C69/743
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process is disclosed for the preparation of an optically active or racemic cyclopropanecarboxylic acid of the formula (I) ##STR1## wherein R.sup.1 and R.sup.2 are the same or different and each is lower alkyl or halogen; PA1 R is a member of a group which contains various cyclic structures as set forth in the specification, PA1 the .about. valency bond represents .alpha.- and/or .beta.-configuration; PA1 the -- valency bond represents .beta.-configuration, PA1 which comprises reacting an optically active or racemic cyclopropanecarboxylic acid of the formula (VII) ##STR2## with a dimethyl-methylidene-ammonium salt of the formula (VIII) ##STR3## wherein X is halogen or lower alkoxy and PA1 Y.sup.- is a halide or lower alkylsulfate ion in an anhydrous, inert organic solvent, and sebsequently reacting a dimethyl-acloxy-methylidene-ammonium salt thus obtained with an optically active, inactive or racemic alcohol of the formula EQU R--OH without isolation, in the presence of an organic base.

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