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。
The Iridium‐catalyzedasymmetrichydrogenation of cyclic sulfamidate imines was successfully developed with N‐methylated ZhaoPhos L2 as the ligand. A variety of chiral cyclic sulfamidates were obtained with excellent results (up to 99% yield, 99% ee). Furthermore, this asymmetrichydrogenation can be employed as the key reaction step to prepare the important intermediates in organic synthesis.
One-Pot Highly Diastereoselective Synthesis of <i>cis</i>-Vinylaziridines via the Sulfur Ylide-Mediated Aziridination and Palladium(0)-Catalyzed Isomerization
cis-trisubstituted vinylaziridines containing a quaternary carbon center is realized by a one-pot protocol in which the combination of sulfur ylide-mediated aziridination of cyclic ketimines and Pd(0)-catalyzedisomerization is employed successfully.
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).