Chiral phosphinamides: new catalysts for the asymmetric reduction of ketones by borane
作者:Barry Burns、N. Paul King、Heather Tye、John R. Studley、Mark Gamble、Martin Wills
DOI:10.1039/a709174e
日期:——
We have identified a new class of catalysts for the asymmetricreduction of prochiral ketones by borane. Key to the architecture of effective catalysts is an N–PO structural unit which may be part of a phosphinamide, phosphonamide or a related structure. Such catalysts are simple to prepare, are often crystalline solids and may be recovered from reduction reactions and reused. The catalysts act essentially
Mild and General Method for the Synthesis of Sulfonamides
作者:José García Ruano、Francisco Yuste、Alejandro Parra、Virginia Mastranzo
DOI:10.1055/s-2007-1000850
日期:2008.1
lowed by 3-chloroperoxybenzoic acid oxidation of the resulting sul- finamides provides primary, secondary, and tertiary alkane-, arene- and heteroarenesulfonamides in high yields. This constitutes a mild and facile experimental protocol that avoids the use of hazardous, unstable, or volatile reagents and does not affect the configurational stability of the amines
Asymmetric Stepwise Reductive Amination of Sulfonamides, Sulfamates, and a Phosphinamide by Nickel Catalysis
作者:Xiaohu Zhao、Haiyan Xu、Xiaolei Huang、Jianrong Steve Zhou
DOI:10.1002/anie.201809930
日期:2019.1.2
Asymmetricreductive amination of poorly nucleophilic sulfonamides was realized in the presence of nickel catalysts and titanium alkoxide. A wide range of ketones, including enolizable ketones and some biaryl ones, were converted into sulfonamides in excellent enantiomeric excess. The cyclization of sulfamates and intermolecular reductive amination of a diarylphosphinamide were also successful. Formic
Asymmetric transfer hydrogenation reactions of <i>N</i>-sulfonylimines by using alcohols as hydrogen sources
作者:Fan Yang、Jingchao Chen、Guoli Shen、Xuexin Zhang、Baomin Fan
DOI:10.1039/c8cc01284a
日期:——
A palladium/zinc co-catalytic system was established and successfully utilized in the asymmetric transfer hydrogenation reactions of N-sulfonylimines with alcohols as hydrogensources. Simple alcohols such as methanol, ethanol and benzyl alcohols are all variable hydrogensources that can reduce various N-sulfonylimines to the corresponding chiral amines with high optical purities in presence of this
Nickel-Catalyzed Asymmetric Transfer Hydrogenation and α-Selective Deuteration of <i>N</i>-Sulfonyl Imines with Alcohols: Access to α-Deuterated Chiral Amines
A nickel-catalyzed enantioselective transferhydrogenation and deuteration of N-sulfonyl imines was developed. Excellent α-selectivity and high deuterium content were achieved by using inexpensive 2-propanol-d8 as a deuterium source. As a highlight, no deuteration of β-C–H and the remote C–H of N-sulfonyl amines occurred, which is hard to achieve using other imines or by hydrogen isotope exchange with