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:
Feb. 23, 1993
Filed:
Jul. 15, 1991
Thomas J Blacklock, Clark, NJ (US);
Todd K Jones, Salan Beach, CA (US);
David J Mathre, Skillman, NJ (US);
Lyndon C Xavier, Edison, NJ (US);
Merck & Co., Inc., Rahway, NJ (US);
Abstract
The chiral catalyst of general structure 1, or its enantiomer ##STR1## is prepared by treating the corresponding N-carboxy anhydride of structure 2 ##STR2## with an aryl metal, especially a phenyl metal such as an aryl magnesium halide, aryl lithium, aryl zinc or aryl cesium, to form a 1,1-diaryl- methanol of structure 3 ##STR3## followed by treatment with a compound of structure, 4 ##STR4## The catalyst, wherein R is aromatic, is novel and in some cases superior to the catalyst wherein R is alkyl or aralkyl in directing the chirality of diborane, borane-dimethyl sulfide or borane-tetrahydrofuran reductions of ketones to secondary alcohols.