title: Regio- and stereoselective 1,2-dihydropyridine alkylation/addition sequence for the synthesis of piperidines with quaternary centers.
abstract: The first example of C alkylation of 1,2-dihydropyridines with alkyl triflates and Michael acceptors was developed to introduce quaternary carbon centers with high regio- and diastereoselectivity. Hydride or carbon nucleophile addition to the resultant iminium ion also proceeded with high diastereoselectivity. Carbon nucleophile addition results in an unprecedented level of substitution to provide piperidine rings with adjacent tetrasubstituted carbon atoms.
authors.affiliation: Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT 06520 (USA).
authors.forename: Simon
authors.initials: S
authors.lastname: Duttwyler
authors.forename: Shuming
authors.initials: S
authors.lastname: Chen
authors.forename: Colin
authors.initials: C
authors.lastname: Lu
authors.forename: Brandon Q
authors.initials: BQ
authors.lastname: Mercado
authors.forename: Robert G
authors.initials: RG
authors.lastname: Bergman
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Ellman
mesh_terms: D000478:Alkylation; D002384:Catalysis; D004095:Dihydropyridines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D015394:Molecular Structure; D010880:Piperidines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D004095:Dihydropyridines; D010880:Piperidines; C032727:piperidine
keywords: alkylation; diastereoselectivity; heterocycles; reduction; synthetic methods