Retracted: Enantioselective Radical Addition to Ketimines: A Synthetic Route Towards α,α-Disubstituted α-Amino Acids
作者:Sang Yoon Kim、Sung Jun Kim、Doo Ok Jang
DOI:10.1002/chem.201002071
日期:2010.11.22
A radical attack: In the presence of a protonated cinchonine derivative, radicaladdition reactions proceeded efficiently, providing a general approach to the synthesis of a diverse range of enantioenriched α,α‐disubstituted α‐amino acids.
The invention concerns a water soluble compound of formula (a) wherein: A represents naphthyl or phenyl; and Ar
1
and Ar
2
independently represent a saturated or aromatic carbocyclic group; X
a
, X
b
are independently selected among an amino group, an ammonium group and an amino group modified by a linear polyoxyalkylene chain, provided that at least one of X
a
and X
b
represents ammonium or modified amino.
Enantioselective hydrogenation of the C:N group: a catalytic asymmetric reductive amination procedure
作者:Mark J. Burk、John E. Feaster
DOI:10.1021/ja00041a067
日期:1992.7
substituents on phosphorus-linked aryl groups dramatically enhance the enantioselectivity. Such electronic effects of ligands on the enantioselectivity are rare, and as in the welldocumented case of Mn(II1)-mediated epoxidation reactions,' these may play an important role in the design of new catalysts. The highest enantioselectivities are obtained in nonpolar solvents (C6F6 = hexane > benzene > THF),
Compounds of formula VII are described:
1
wherein A represents phenyl or naphthyl and
Ar
1
and Ar
2
independently represent a saturated or aromatic carbocyclic group. The compounds may be prepared by reducing the nitrile functions of a compound of formula I:
2
描述了式 VII 的化合物:
1
其中 A 代表苯基或萘基,且
Ar
1
和 Ar
2
分别代表饱和或芳香碳环基团。这些化合物可通过还原式 I 化合物的腈基官能团来制备:
2