Gold-silver catalyzed straightforward one pot synthesis of pyrano[3,4-b]pyrrol-7(1H)-ones.

Pyrano[3,4-b]pyrrol-7(1H)-one is a bicyclic structure that is rarely described in the literature but is found in numerous polycyclic natural products as lamellarins. This work presents a one-pot synthesis of pyrano[3,4-b]pyrrol-7(1H)-one substituted in the 2- and 5-position. The reaction proceeds via a one-pot two step 5-endo-dig and 6-endo-dig cyclization catalyzed by a cationic gold complex with high regioselectivity.

Regiocontrolled functionalization of 2,3-dihalogenoimidazo[1,2-a]pyridines by Suzuki-Miyaura and Sonogashira cross-coupling reactions.

An efficient method for regiocontrolled functionalization of 2,3-dihalogenoimidazo[1,2-a]pyridine was developed. This sequence allowed the selective introduction of aryl, heteroaryl, alkyl and alkynyl substituents at both 2- and 3-positions, by using Suzuki-Miyaura and Sonogashira cross-coupling reactions. A library of compounds diversely substituted on 2- and 3-positions can be easily prepared from a common, stable and easily accessible starting material.