Controlled Diastereo- and Enantioselection in a Catalytic Asymmetric Aziridination
作者:Aman A. Desai、William D. Wulff
DOI:10.1021/ja1038648
日期:2010.9.29
the development of an unprecedented universal catalyticasymmetricaziridination protocol. The substrate scope is broad and includes iminespreparedfrom both electron-rich and electron-poor aromatic aldehydes and also from 1°, 2°, and 3° aliphatic aldehydes. The face selectivity of the addition to the imine was found to be independent of the diazo compounds. The (S)-VANOL or (S)-VAPOL derived catalyst
The easily obtained and very stable title compound 1 can be used for direct diazoacetylation of aromatic or aliphatic amines, phenols, thiophenol, and peptides under mild conditions.
Trans-Selective Asymmetric Aziridination of Diazoacetamides and <i>N</i>-Boc Imines Catalyzed by Axially Chiral Dicarboxylic Acid
作者:Takuya Hashimoto、Nanase Uchiyama、Keiji Maruoka
DOI:10.1021/ja805635c
日期:2008.11.5
Axially chiral dicarboxylic acid (R)-1d catalyzed reaction of diazoacetamides and N-Boc imines provided a novel organocatalytic means for the formation of enantiomerically enriched N-Boc protected trans aziridines.
Highly Efficient Asymmetric <i>Trans-</i>Selective Aziridination of Diazoacetamides and <i>N</i>-Boc-imines Catalyzed by Chiral Brønsted Acids
A clean and fast (10 min) aziridination of diazoacetamides with N-Boc-imines, as well as N-Cbz-imines, catalyzed by chiral phosphoric acid (R)-5g in DCM at room temperature was developed, The excellent yields (89-97%), diastereoselectivities (trans/cis > 50:1), chemoselectivities (3:4 = >95:5), and enantioselectivities (88-98% ee) were achieved in the reaction.