title: Facial and Efficient Access to Dihydropyrano[3,2-c]Chromenes via Three-Component Reaction Using N,N-Dimethylbenzylamine As a New Organocatalyst.
abstract: The N,N-dimethylbenzylamine (DMBA), as an efficient and commercially available organocatalyst was employed for the one-pot synthesis of dihydropyrano[3,2-c]chromene derivatives in ethanol medium. In this work, the one-pot Knoevenagel-Michael-Thorpe-Ziegler type cascade heterocyclization has been developed for the synthesis of dihydropyrano[3,2-c]chromene-containing heterocycles from the one-pot multicomponent condensation reaction of 4-hydroxycoumarin, malononitrile/ethyl cyanoacetate, and various aldehydes at 60°C. The salient features of this basecatalyzed reaction are mild reaction conditions, reusability of the reaction medium, shorter reaction times, and easy separation of the reaction mixture.
authors.affiliation: School of Chemistry, Damghan University, P.O. Box: 36719-41167, Damghan, Iran. hkiyani@du.ac.ir.
authors.forename: Hamzeh
authors.initials: H
authors.lastname: Kiyani
authors.forename: Mozhgan Sadat
authors.initials: MS
authors.lastname: Jalali
mesh_terms: D015110:4-Hydroxycoumarins / Q000737:chemistry; D000085:Acetates / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry; D001578:Benzopyrans / Q000138:chemical synthesis*; D001596:Benzylamines / Q000737:chemistry*; D002384:Catalysis; D002867:Chromones / Q000138:chemical synthesis*; D003500:Cyclization; D009570:Nitriles / Q000737:chemistry
chemical_list: D015110:4-Hydroxycoumarins; D000085:Acetates; D000447:Aldehydes; D001578:Benzopyrans; D001596:Benzylamines; D002867:Chromones; D009570:Nitriles; C543205:dihydropyranochromone; C000945:dicyanmethane; C045966:N-benzyl-N,N-dimethylamine; C068805:4-hydroxycoumarin; C007659:ethyl cyanoacetate