Process for resolution of optical isomers
US4463176A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1982 |
| Grant date | Jul 31, 1984 |
| Priority date | — |
| Expiry date | Sep 13, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C275/24
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for resolving a racemic modification of .beta.-adrenergic aryl- or hetaryl-oxypropanolamines such as (.+-.)-2-[2-hydroxy-3-[[2-(1H-indol-3-yl)-1,1-dimethylethyl]amino]propoxy] benzonitrile into its individual enantiomers is described. The process comprises converting the racemic modification into a pair of diastereomeric urea derivatives by reaction with a chiral aralkylisocyanate; separation into the individual diastereomers; and facile regeneration of the starting amine by cleavage of the intermediate urea compound using hydrazine. This final step is improved by the addition of an .alpha.-keto carboxylic acid, such as pyruvic acid, which functions as a scavenger of nucleophilic by-products.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.