Catalytic Enantioselective Addition of Dialkylzinc to <i>N</i>-Diphenylphosphinoylimines. A Practical Synthesis of α-Chiral Amines
作者:Alessandro A. Boezio、André B. Charette
DOI:10.1021/ja027673x
日期:2003.2.19
The enantioselectiveaddition of dialkylzincreagents to N-diphenylphosphinoylimines derived from aryl-, furyl-, and cyclopropylaldehydes is efficiently catalyzed by a copper(II) triflate/(R,R)-MeDUPHOS complex. The yields are high (51-98%), and the enantiomeric excesses vary from 85 to 96%. This route provides a practical route to alpha-chiral amines.
Polymer-supported l-prolinol-based catalysts for the enantioselective addition of dialkylzinc reagents to N-(diphenylphosphinyl)imines
作者:Raquel Almansa、Juan F. Collados、David Guijarro、Miguel Yus
DOI:10.1016/j.tetasy.2012.12.007
日期:2013.2
Merrifield or Wang-type resins have been shown to form efficient catalysts for the enantioselective addition of dialkylzinc reagents to N-(diphenylphosphinyl)imines. The enantioselectivity achieved with the polymeric catalyst (ee up to 88%) is slightly lower than the one obtained with the homogeneous ligand N-benzyl-l-prolinol, but the polymer-supported ligand presents the advantage of its recyclability: it
The present invention relates to a method of enantioselective addition to imines, including: reacting R
3
CH═NY with R
4
ZnR
5
in the presence of a compound represented by the following formula (I),
in which Y, R
1
, R
2
, R
3
, R
4
and R
5
are defined the same as the specification. Accordingly, the present invention can prepare secondary amines in high yields and enantiomeric excess by the above-mentioned method.
Enantioselective Addition of Dialkylzinc to Aromatic Aldimines Mediated by Camphor-Derived Chiral β-Amino Alcohols
作者:Wei-Ming Huang、Biing-Jiun Uang
DOI:10.1002/asia.201403240
日期:2015.4
The enantioselective addition of diethylzinc or dimethylzinc to N‐(diphenylphosphinoyl)imines mediated by 1 or 2 could be achieved in high yields (70–97 %) and enantioselectivities (85–98 % ee). The catalytic loading of 1 or 2 a could be reduced to 10 mol % for methylation or ethylation of imines in high yields and enantioselectivities (79–96 %) when the reaction was conducted in the presence of 1
Preparation and Use of Aziridino Alcohols as Promoters for the Enantioselective Addition of Dialkylzinc Reagents to <i>N</i>-(Diphenylphosphinoyl) Imines
作者:Pher G. Andersson、David Guijarro、David Tanner
DOI:10.1021/jo970918h
日期:1997.10.1
chiral aziridino alcohols 2-5 has been synthesized starting from either readily available amino acids (L-serine, L-threonine, and allo-L-threonine) or simple olefins (using Sharpless asymmetric aminohydroxylation and dihydroxylation reactions). Chiral ligands 2-5 have been tested as promoters for the enantioselective addition of dialkylzinc reagents to N-(diphenylphosphinoyl) imines 1. The influence