Enantioselective Direct Amination of α-Cyanoacetates Catalyzed by Bifunctional Chiral Ru and Ir Amido Complexes
作者:Yasuharu Hasegawa、Masahito Watanabe、Ilya D. Gridnev、Takao Ikariya
DOI:10.1021/ja710273s
日期:2008.2.1
The bifunctional chiral amido Ir complex catalyzed asymmetric electrophilic direct amination of alpha-substituted alpha-cyanoacetates using azodicarboxylates proceeds rapidly to provide the corresponding hydrazine adducts in high yields and with excellent ea values.
Asymmetric Construction of Quaternary Stereocenters by Direct Organocatalytic Amination of α-Substituted α-Cyanoacetates and β-Dicarbonyl Compounds
作者:Steen Saaby、Marco Bella、Karl Anker Jørgensen
DOI:10.1021/ja047704j
日期:2004.7.1
The first organocatalytic highly enantioselective reactions of substituted alpha-cyanoacetates and beta-dicarbonyl compounds with azodicarboxylates are reported. In the presence of 0.1-5 mol % of a quinidine-derived alkaloid beta-ICD, optically active quaternary hydrazine adducts are obtained in very high yields and with enantioselectivities up to >98% ee. A two-step procedure for the cleavage of the hydrazine N-N bond using SmI2 is also demonstrated.