Process for preparing 5-aroyl 1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acids and novel intermediates therein
US4347187A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1981 |
| Grant date | Aug 31, 1982 |
| Priority date | — |
| Expiry date | Jun 11, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D207/36
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
5-Substituted-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acids of the formula ##STR1## wherein: X is hydrogen, lower alkyl, chloro or bromo; Ar is a moiety selected from the group consisting of ##STR2## in which: Y is oxygen or sulfur; PA0 R is hydrogen, methyl, chloro, or bromo, the R substitution being at the 3, 4 or 5 position of the ring; PA0 R.sup.1 is hydrogen, lower alkyl, lower alkoxyl, lower alkoxycarbonyl, lower alkylcarbonyl, fluoro, chloro or bromo, the R.sup.1 substitution being at any available position in the ring; PA0 R.sup.2 is hydrogen or lower alkyl; are prepared by .beta.-decarboxylation of the corresponding dialkyl-1,1-dicarboxylates. Certain substituted pyrroles are useful as intermediates for preparing the compounds of formula I.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.