使用HCO 2 H / Et 3 N混合物作为氢源和定义明确的手性Rh催化剂(S,S)-或(R,R)-2,对环状氨基磺酸亚胺4和9进行不对称转移氢化(ATH), Cp * RhCl(TsDPEN)可在室温下0.5h内以优异的收率和对映选择性有效生产相应的环状氨基磺酸酯。具有预先存在的立体生成中心的4,5-二取代的亚胺9的ATH显示以动态动力学拆分发生。
Enantioselective Rhodium-Catalyzed Arylation of Cyclic <i>N</i>-Sulfamidate Alkylketimines: A New Access to Chiral β-Alkyl-β-aryl Amino Alcohols
作者:Ya-Jing Chen、Ya-Heng Chen、Chen-Guo Feng、Guo-Qiang Lin
DOI:10.1021/ol501464e
日期:2014.6.20
The enantioselectiverhodium-catalyzed1,2-addition of arylboronates to cyclic N-sulfamidate alkylketimines was developed. With a rhodium/diene complex as catalyst, high enantioselectivity and broad functional group tolerance were observed. The resulting sulfamidates can easily be converted into chiral β-alkyl-β-aryl amino alcohols.
Using Pd(CF3CO2)(2)/(SS)-f-binaphane as the catalyst, an efficient enantioselective synthesis of cyclic sulfamidates was developed via asymmetric hydrogenation of the corresponding cyclic imines in 2,2,2-trifluoroethanol at room temperature with high enantioselectivities (up to 99% ee).