Stripping off Water at Ambient Temperature: Direct Atom-Efficient Acetal Formation between Aldehydes and Diols Catalyzed by Water-Tolerant and Recoverable Vanadyl Triflate
作者:Chien-Tien Chen、Shiue-Shien Weng、Jun-Qi Kao、Chun-Cheng Lin、Mi-Dan Jan
DOI:10.1021/ol051178z
日期:2005.7.1
catalyst can be readily recovered from the aqueous layer. In combination with vanadyl triflate-catalyzed sequential regioselective, reductive acetal opening and chemoselective acylations, the title method allows for differential functionalization of all four hydroxyl units in a given glucopyranoside.
[反应:请参见文字]。通过使用三氟甲磺酸钒在环境温度下在CH(3)CN中作为催化剂,可以很容易地用1,2-和1,3-二醇将芳香醛保护为缩醛。基于碳水化合物的1,2-和1,3-二醇同样可以得到很好的保护。催化剂可以容易地从水层中回收。与三氟甲磺酸氧钒催化的顺序区域选择性,还原性乙缩醛开放和化学选择性酰化相结合,该标题方法可在给定的吡喃葡萄糖苷中实现所有四个羟基单元的差异化功能化。