Catalyst-Controlled Regiodivergent Synthesis of 1- and 3-Thiosugars with High Stereoselectivity and Chemoselectivity
作者:Yuexin Liu、Yang Jiao、Huajun Luo、Nianyu Huang、Mengnan Lai、Kun Zou、Hui Yao
DOI:10.1021/acscatal.1c00225
日期:2021.5.7
An effective regiodivergent synthesis toward 1- and 3-thiosugars was achieved through palladium and cobalt catalysis, respectively. β-1-Thiosugars were obtained from 3,4-O-carbonate-glycals and various thiols catalyzed by Pd2(dba)3 in good yields with exclusive stereoselectivity and chemoselectivity, while only (3S)-3-thiosugars were generated via Co(BF4)2. Experiments and DFT calculations supported
通过钯和钴催化分别实现了对1-硫代糖和3-硫代糖的有效区域发散合成。从3,4- O-碳酸盐-糖和Pd 2(dba)3催化的各种硫醇以良好的产率获得β-1-硫代糖醇,并具有独有的立体选择性和化学选择性,而仅通过生成(3 S)-3-硫代糖钴(BF 4)2。实验和DFT计算支持所提出的机理,即在Pd条件下,硫醇基团更愿意与C4-氧从上表面形成氢键,而在Co条件下,硫醇会与钴从下表面形成氢键。关键中间体的Pd / Co-C1和Pd / Co-C3键长之间的差异为1,3-区域选择性提供了进一步的见解。