An organocatalytic method for constructing pyrroles the cycloisomerisation of -1-iodo-4--methylbenzenesulfonyl-1,6-enynes

A new cycloisomerisation of Z -1-iodo-4- N -methylbenzenesulfonyl-1,6-enynes to functionalized pyrroles was realized in the presence of an organomolecule (4,4′-bis(1,1-dimethylethyl)-2,2′-bipyridine) and KO t Bu. The transformations were performed efficiently to produce different kinds of functionalized pyrroles within 10 min. This is the first example of an organomolecule promoted methodology with vinyl iodides from a non-aromatic system to an aromatic system, which offers an excellent option toward establishing a new horizon for cross-coupling reactions of vinyl halides. Preliminary mechanistic studies were performed and a crude radical pathway was proposed. A new cycloisomerisation of Z -1-iodo-4- N -methylbenzenesulfonyl-1,6-enynes to functionalized pyrroles was realized in the presence of an organomolecule (4,4′-bis(1,1-dimethylethyl)-2,2′-bipyridine) and KO t Bu.