Methods for producing N-protected-azetidine-2-carboxylic acids
US6313315A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 2000 |
| Grant date | Nov 6, 2001 |
| Priority date | — |
| Expiry date | Jun 1, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D205/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
There is disclosed a method for producing an essentially enantiomerically pure N-protected-azetidine-2-carboxylic acid of formula (1): ##STR1## which method is characterized by: PA1 subjecting a crude enantiomerically excess N-protected-azetidine-2-carboxylic acid comprising said enantiomer represented by formula (1) in excess to the other enantiomer thereof to crystallization in an organic solvent selected from aromatic hydrocarbon, aliphatic ether, aliphatic alcohol, aliphatic ketone, aliphatic nitrile, aliphatic amide, aliphatic sulfoxide, aliphatic ester and a mixed solvent thereof, PA1 wherein R is: PA2 an optionally substituted alkyl, alicyclic or alicyclicalkyl group, PA2 an optionally substituted alkenyl group, PA2 an optionally substituted aryl group, PA2 an optionally substituted heteroaryl group, or PA2 a dialkylamino group, and PA2 absolute configuration of the asterisked asymmetric carbon atom is S or R.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.