Copper Catalyst-Promoted Regioselective Multicomponent Cascade Cyclization of 3-Aza-1,5-enynes with Sulfur Dioxide and Cycloketone Oxime Esters to Access Cyanoalkylsulfonylated 1,2-Dihydropyridines
Ran Ding, Bing Zhang, Le Yang, Tao Ma, Dong Gang, Yueyuan Mao, Hui Gao
Abstract
Radical cascade cyclization via the cracking of alkenyl C-H has emerged as an attractive and remarkable tool for the rapid construction of ring frameworks with endocyclic double bonds. We developed a cascade reaction of 3-aza-1,5-enynes with sulfur dioxide and cycloketone oxime esters to access cyanoalkylsulfonylated 1,2-dihydropyridines, which can be easily converted to pyridine derivatives. This protocol involves radical addition to the C≡C bond and 6-endo cyclization and features high regioselectivity and a broad substrate scope.
Topics & Concepts
ChemistryRegioselectivityOximeCatalysisRadical cyclizationRing (chemistry)PyridineSulfurCascade reactionCascadeSubstrate (aquarium)Combinatorial chemistryOrganic chemistryMedicinal chemistryGeologyChromatographyOceanographySulfur-Based Synthesis TechniquesCatalytic C–H Functionalization MethodsChemical Synthesis and Reactions