A facile and efficient one-pot, multicomponent synthesis of 4H-chromenes is reported, through the reaction of arylglyoxalmonohydrates with 1,3-diketones and malononitrile in eTEMPthanol in the presence of L-proline as a catalyst.

An efficient method to synthesis the 2H-pyrans using three component reactions of dithiocarbamats, activated acetylenes and isocyanides in water as the solvent is described. In these reactions, synthesis of 2H-pyrans is possible based on the one-pot reaction and without using any catalyst. The mild reaction conditions and high yields of the products exhibit synthetic advantage of these methods.

a simple and efficient one-pot, three-component strecker reaction of protected amino acids, aromatic aldehydes, and trimethylsilyl cyanide has been developed for the synthesis of chiral α-amino nitriles. the reaction was carried out in the presence of catalytic amount of phosphotungstic acid (h3[p(w3o10)4]) as an environmentally friendly catalyst.

1,3-dibromo-5,5-dimethylhydantoin (dbh) and benzyltriphenylphosphoniumtribromide (btptb) were used as efficient catalysts for the promotion of the synthesis of 1,8-dioxo-octahydroxanthene derivatives (doxos) via a one-pot three component condensation of aldehydes and cyclic 1,3-dicarbonyl compounds in the absence of solvent.