The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 1993
Filed:
Mar. 11, 1992
Josef Meier, Burghausen, DE;
Wacker-Chemie GmbH, Munich, DE;
Abstract
The invention relates to a process for the preparation of .beta.-ketocarboxylic acid esters of the general formula ##STR1## in which R.sup.1 is an alkyl radical having 1 to 4 C atoms, R.sup.2 is an alkyl radical or alkenyl radical having 2 to 15 C atoms or a phenyl radical and R.sup.3 is hydrogen or an alkyl or alkenyl radical having 1 to 6 C atoms, characterized in that acetocarboxylic acid esters of the general formula ##STR2## in which R.sup.1 and R.sup.3 are as defined, are reacted with calcium hydroxide or calcium oxide in the presence of an organic solvent and in the absence of water, the calcium chelate complexes formed are acylated with carboxylic acid chloride and the products are then cleaved with aqueous ammonium salt solution to form the .beta.-ketocarboxylic acid esters of formula (I). The .beta.-ketocarboxylic acid esters readily accessible by the process according to the invention can be used as important intermediates in the synthesis of pharmaceutically active ingredients or plant protection agents.