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. 13, 2001
Filed:
Jan. 19, 2000
Applicant:
Inventors:
Franz Dietrich Klinger, Griesheim, DE;
Lienhard Wolter, Hochstetten/Dhaun, DE;
Wolfgang Dietrich, Bad Kreuznach, DE;
Assignee:
Boehringer Ingelheim Pharma KG, Ingelheim, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
C07C / ;
Abstract
The present invention relates to an improved process for preparing L-phenylephrine hydrochloride 3 on an industrial scale by asymmetric hydrogenation as the key step and a special sequence of subsequent steps, using [Rh(COD)Cl],as catalyst and a chiral, two-pronged phosphine ligand such as (2R,4R)-4-(dicyclohexylphosphino)-2-(diphenylphosphino-methyl)-N-methyl-aminocarbonyl-pyrrolidine as the catalyst system.