A New Method for the Synthesis of Multisubstituted Pyrroles of Biological Interest by Double Nucleophilic Addition to α,β‐Unsaturated Imines

Abstract

Double nucleophilic addition reactions of dialkoxy ketenesilyl acetals proceeded with α,β‐unsaturated imines to give 1,4‐ and 1,2‐double addition products, and their subsequent transformations afforded multisubstituted pyrroles in good yields. Application of this procedure to the synthesis of an imidazole glycerol phosphate dehydratase inhibitor (IGPDI), a physiologically active 2,3,5‐trisubstituted pyrrole, is also described.

One-Pot Synthesis of Pyrrole-2-carboxylates and -carboxamides via an Electrocyclization/Oxidation Sequence

“…Other methods build up the five-membered ring and adjust the oxidation stage by a dehydrogenation of a 4,5-, 3,4-, and 2,5-dihydropyrrole intermediate. The most common oxidants that have been used in this context are chloranil, Pd/C, , MnO 2 , CrO 3 , FeCl 3 , and DDQ. , Generally, these methods were applied to isolated dihydropyrroles. Here, we report a one-pot synthesis of pyrrole-2-carboxylates − and -carboxamides from enones and glycine esters or amides that is based on the oxidation of 3,4-dihydropyrrole intermediates formed in a spontaneous 6π-electrocyclization.…”

Metal-free, one-pot conversion of proline derivatives into 2-aryl-3-iodo pyrrolidines by a sequential scission–iodination–arylation process

“…by conventional methodologies to provide a diversity of 2-arylpyrrolidines. 22 Alternatively, they can be readily oxidized to pyrroles Organic & Biomolecular Chemistry Paper with DDQ, 23 as shown with the conversions of compounds 22 and 24 (Scheme 3) to the pyrrole derivatives 28 and 29 in good yields. The saponification of these pyrroles afforded the unprotected 2-aryl pyrroles 30 and 31.…”

“…Benzyl 2-(2-methoxyphenyl)-2,5-dihydro-1H-pyrrole-1-carboxylate (23). Obtained from benzyl 3-iodo-2-(2-methoxyphenyl)-pyrrolidine-1-carboxylate (15) (153 mg, 0.35 mmol) according to the general procedure for the generation of dihydropyrroles, Method A.…”