title: Acyclic chiral amines and amino acids as inexpensive and readily tunable catalysts for the direct asymmetric three-component Mannich reaction.
abstract: The direct three-component asymmetric Mannich reaction catalyzed by acyclic chiral amines or amino acids is presented. Simple acyclic chiral amines and amino acids--such as alanine-tetrazole (9), alanine, valine, and serine-catalyzed the three-component asymmetric Mannich reactions between unmodified ketones, p-anisidine, and aldehydes with high chemo- and stereoselectivity, furnishing the corresponding Mannich bases with up to >99 % ee. This study demonstrates that the whole range of amino acids in nature, as well as nonproteogenic amino acid derivatives, can be considered in the design and tuning of novel, inexpensive organocatalysts for the direct asymmetric Mannich reaction.
authors.affiliation: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
authors.forename: Ismail
authors.initials: I
authors.lastname: Ibrahem
authors.forename: Weibiao
authors.initials: W
authors.lastname: Zou
authors.forename: Magnus
authors.initials: M
authors.lastname: Engqvist
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Xu
authors.forename: Armando
authors.initials: A
authors.lastname: Córdova
mesh_terms: D000588:Amines / Q000737:chemistry*; D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013237:Stereoisomerism
chemical_list: D000588:Amines; D000596:Amino Acids