Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Chem Asian J. 2020 Nov 16;15(22):3820-3824. doi: 10.1002/asia.202001090. Epub 2020 Oct 16.
A newly devised radical-based strategy enabled coupling between multiply oxygenated α-alkoxyacyl tellurides and 2-hydroxybenzaldehyde derivatives. A reagent combination of Et B, Et AlCl, and O promoted the formation of the α-alkoxy carbon radical from the α-alkoxyacyl telluride and the addition of the radical to the carbonyl group of 2-hydroxybenzaldehyde. The reaction chemo- and stereoselectively forged the hindered C-C bond between two oxygen-functionalized carbons at ambient temperature. The method was applied to the preparation of 12 coupling adducts with three to six contiguous stereocenters and to the concise synthesis of an antitumor compound, LLY-283.
一种新设计的基于自由基的策略实现了多氧代α-烷氧基酰基碲化物与 2-羟基苯甲醛衍生物的偶联。Et B、Et AlCl 和 O 的试剂组合促进了α-烷氧基酰基碲化物中α-烷氧基碳自由基的形成，以及自由基与 2-羟基苯甲醛羰基的加成。反应具有化学和立体选择性，在环境温度下在两个氧官能化碳之间形成受阻的 C-C 键。该方法用于制备 12 个具有三个到六个连续立体中心的偶联加合物，并用于抗肿瘤化合物 LLY-283 的简洁合成。
