Chemoselective allylic addition of allyltrichlorosilane to α-oxocarboxylic acids: synthesis of tertiary α-hydroxy carboxylic acids
摘要:
Allyltrichlorosilane can add to alpha-oxocarboxylic acids in the presence of DMF and HMPA. The alpha-carboxylic substituent exerts a remarkable neighboring group effect on the reaction, The reaction presumably proceeds in an intramolecular fashion through a 'rigid' bicyclic transition state assembly involving a hypervalent silicate species, which produces the chemoselectivity approaching 100%. (C) 2000 Dupont Pharmaceuticals Company. Published by Elsevier Science Ltd. All rights reserved.