title: Organocatalytic Nucleophilic Addition of Hydrazones to Imines: Synthesis of Enantioenriched Vicinal Diamines.
abstract: In the presence of a catalytic amount of chiral phosphoric acid, nucleophilic addition of N-monosubstituted hydrazones to N-Boc imines affords differentially protected vicinal diamines in the form of β-amino N,N'-dialkyldiazenes in excellent yields with high chemo-, diastereo-, and enantioselectivity. This catalytic asymmetric aza-Mannich reaction represents the first example in which N-alkyl hydrazones serve as α-azo carbanion equivalents to provide vicinal diamines with control of the two contiguous stereocenters. The adducts are readily converted into the monoprotected or free diamines and derivatives thereof.
authors.affiliation: Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland.
authors.forename: Jieping
authors.identifier: 0000-0002-8390-6689
authors.initials: J
authors.lastname: Zhu
keywords: Mannich reactions; asymmetric reactions; diamines; hydrazones; organocatalysis