Radical-mediated hydroxyalkylation of α,β-unsaturated esters
摘要:
The radical-mediated hydroxyalkylation of alpha,beta-unsaturated esters with alkyl iodides, trialkylborane, water and KF in THF gave the corresponding alpha-hydroxy esters. The synthetic advantage of the method was demonstrated by a short-step total synthesis of (+/-)-tanikolide. (c) 2005 Elsevier Ltd. All rights reserved.
We report a concise synthesis of tanikolide 1, which was obtained from ethyl2-oxocyclopentanecarboxylate in four steps: alkylation, Baeyer–Villiger reaction, saponification, and reduction/lactonization, in 70% overall yield. Our strategy should be suitable for the preparation of 1 in multigram or larger quantities. The net result of the last two steps (i.e. saponification and reduction/lactonization)