80965-04-4Relevant articles and documents
Process for preparing 5-aroyl 1,2-dihydro-3-H pyrrolo[1,2-a]pyrrole-1-carboxylic acids and novel intermediates therein
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, (2008/06/13)
5-Substituted-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acids of the formula STR1 wherein: X is hydrogen or lower alkyl; Ar is a moiety selected from the group consisting of STR2 in which: Y is oxygen or sulfur; R is hydrogen, methyl, chloro, or bromo, the R substitution being at the 3, 4 or 5 position of the ring; R1 is hydrogen, lower alkyl, lower alkoxyl, lower alkoxycarbonyl, lower alkylcarbonyl, fluoro, chloro or bromo, the R1 substitution being at any available position in the ring; R2 is hydrogen or lower alkyl; are prepared by β-decarboxylation of the corresponding dialkyl-1,1-dicarboxylates. Certain substituted pyrroles are useful as intermediates for preparing the compounds of formula I.
Novel Syntheses of 5-Aroyl-1,2-dihydro-3H-pyrrolopyrrole-1-carboxylic Acids
Franco, Fidencio,Greenhouse, Robert,Muchowski, Joseph M.
, p. 1682 - 1688 (2007/10/02)
A fundamentally new approach to the synthesis of the title compounds was devised in which the crucial step was the intramolecular displacement of methanesulfinate ion or bromide ion by the sodium enolates of properly disposed substituted malonate esters such as 13a-13c and 20.As integral parts of the above process, a new four-carbon alkylation of the pyrrole nitrogen atom, a novel synthesis of 2-(methylthio)pyrroles, and the use of the dimethylsulfonium moiety as meta directing group in the pyrrole system were developed.
