| Abstract: | A convenient, large-scale synthesis of the antibiotic pyoluteorin, 2,3-dichloro-5-(2′,6′-dihydroxybenzoyl)-pyrrole ( 1 ), is described. A key step in the synthesis involved a Friedel-Crafts aroylation of pyrrole with 2,6-dimethoxybenzoyl chloride ( 3 ) in methylene chloride. The desired intermediate, 2-(2′,6′-dimethoxybenzoyl)pyrrole ( 4 ), was obtained as the major product, along with a product of beta substitution ( 6 ). Compound 4 was converted to pyoluteroin ( 1 ) in four steps in an overall yield of 51%. |
