title: Cesium effect: high chemoselectivity in direct N-alkylation of amines.
abstract: A novel method for the mono-N-alkylation of primary amines, diamines, and polyamines was developed using cesium bases in order to prepare secondary amines efficiently. A cesium base not only promoted alkylation of primary amines but also suppressed overalkylations of the produced secondary amines. Various amines, alkyl bromides, and alkyl sulfonates were examined, and the results demonstrated this methodology was highly chemoselective to favor mono-N-alkylation over dialkylation. In particular, use of either sterically demanding substrates or amino acid derivatives afforded the secondary amines exclusively, offering wide applications in peptidomimetic syntheses.
authors.affiliation: Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, Tampa, Florida 33620-5250, USA.
authors.forename: Ralph Nicholas
authors.initials: RN
authors.lastname: Salvatore
authors.forename: Advait S
authors.initials: AS
authors.lastname: Nagle
authors.forename: Kyung Woon
authors.initials: KW
authors.lastname: Jung
mesh_terms: D000478:Alkylation; D000588:Amines / Q000737:chemistry*; D002586:Cesium / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D018716:Molecular Mimicry; D010455:Peptides / Q000737:chemistry
chemical_list: D000588:Amines; D010455:Peptides; D002586:Cesium