Gupta Mukul R, Thakur Kratima, Khare Naveen K
Department of Chemistry, University of Lucknow, Lucknow, 226007, India.
Department of Chemistry, University of Lucknow, Lucknow, 226007, India.
Carbohydr Res. 2018 Mar 2;457:51-55. doi: 10.1016/j.carres.2018.01.003. Epub 2018 Jan 31.
Glucal with different alcohols can be converted into the corresponding 2-deoxy glycosides without Ferrier rearrangement in high yield by treatment with eco friendly transition metal based catalysts [CuCl·2HO-NaI (A) or CeCl·7HO-NaI (B)] and chiral amine ligand L-proline at various reaction conditions which were optimized for stereoselectivity. The catalyst CeCl·7HO-NaI (B) and ligand L-proline in toluene, was found to be much more efficient and high atom economic for the stereoselective glycosidation of propargyl alcohol with glucal, afforded exclusively α-2-deoxy propargyl glycoside in 98% optimized yield. The ligand L-proline was used for the first time in stereoselective glycosidation of α-2-deoxy glycosides involving glucal and alcohols.
在各种为立体选择性优化的反应条件下，通过使用环境友好的过渡金属基催化剂[CuCl·2H₂O - NaI (A) 或 CeCl₃·7H₂O - NaI (B)]和手性胺配体L - 脯氨酸，不同醇类的葡糖醛可以在不发生费里尔重排的情况下高产率地转化为相应的2 - 脱氧糖苷。发现催化剂CeCl₃·7H₂O - NaI (B)和配体L - 脯氨酸在甲苯中，对于炔丙醇与葡糖醛的立体选择性糖基化反应更高效且原子经济性高，以98%的优化产率独家提供α - 2 - 脱氧炔丙基糖苷。配体L - 脯氨酸首次用于涉及葡糖醛和醇类的α - 2 - 脱氧糖苷的立体选择性糖基化反应。
