Process for the preparation of pyrrolidone derivatives
US4797496A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1988 |
| Grant date | Jan 10, 1989 |
| Priority date | — |
| Expiry date | Mar 8, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D233/32
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Process for preparing pyrrolidinone derivatives of (1) ##STR1## in which R is hydrogen, alkyl or acyl characterized in that a compound of (2) ##STR2## wherein R.sup.1 is hydrogen and R.sup.2 is benzyl or substituted benzyl, or R.sup.1 and R.sup.2 can together form a group ##STR3## where R.sup.4 and R.sup.5 are independently hydrogen, alkyl, phenyl or optionally substituted aryl or together are 1,4-butylene or 1,5-pentylene; R.sup.3 is hydrogen or straight or branched alkyl of 1 to 4 carbon atoms; and X is alkyl subjected to N-deprotection and the deprotected intermediate is cyclized intramolecularly. The deprotected intermediates can be isolated as acid-addition salts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.