Oxidation on the Side Chain in 1,2-Dialkyl-3-nitropyrroles and 3-Alkylaminosulfonyl-1,2-dialkylpyrroles

Abstract

Benzylic-type methyl and methylene groups can be converted either to the corresponding alkyl halide, alcohol or carbonyl compounds by treating different substituted 3-nitro-and 3-alkylaminosulfonylpyrroles with the adequate oxidizing agent.

Synthesis of Highly Substituted Pyrroles via a Multimetal-Catalyzed Rearrangement−Condensation−Cyclization Domino Approach

“…The method described above is particularly attractive for assembling 5-methylpyrrole-3-carboxylates 3 , as subsequent functionalization of the methyl group in the 5-position has the potential to access further synthetic applications. Examples to modify the C5-Me include halogenations, alkylations, and Mannich reactions as well as partially practical oxidations to aldehydes . Gratifyingly, we found that 2-iodoxybenzoic acid (IBX) is an excellent reagent for the selective oxidation to generate synthetically useful 5-formylpyrroles.…”

Five‐Membered Heterocycles: Pyrrole and Related Systems

“…An alternative route to pyrrole-2-carboxaldehydes involves oxidative cleavage of 2-(polyhydroxyalkyl)pyrroles with CAN [361]. In cases where the pyrrole nucleus is strongly deactivated, oxidation of an aldehyde functionality at C2 to the corresponding carboxylic acid may be achieved using the strong oxidant KMnO 4 [362]. A useful oxidative coupling reaction has been elaborated, providing access to quarter-, penta-and sexipyrrole derivatives.…”