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:
Aug. 25, 1987
Filed:
Feb. 20, 1986
Masato Tanaka, Yatabe, JP;
Kanji Ohtsuka, Tokyo, JP;
Abstract
The invention provides an improvement in the method for the preparation of phenyl pyruvic acid by the reaction of benzyl chloride and carbon monoxide in a liquid reaction medium in the presence of a cobalt carbonyl as the catalyst. In the inventive method, the reaction is performed in the presence of calcium hydroxide and the reaction medium is a binary system composed of water and an organic solvent capable of dissolving the catalyst and not freely miscible with water. The reaction can proceed even under normal pressure and the desired product can be readily recovered in the form of precipitates of the calcium salt while the catalyst dissolved in the organic phase after completion of the reaction can be recycled and re-used as such in the next run so that the costs for the catalyst regeneration in the prior art can be entirely saved.