using a combination of hypervalent iodine(III) reagent, molecular iodine, and a base. This method offers an efficient synthesis of 2-acyl furans with diverse substitutionpatterns in a regioselective manner under mildreaction conditions. A mechanistic proposal for these transformations involving alkyne activation by trifluoroacetylhypoiodite generated in situ is presented.
A general and efficient synthesis of substituted furans and dihydrofurans via gold-catalyzed cyclization of (Z)-2-en-4-yn-1-ols
作者:Xiangwei Du、Feijie Song、Yuhua Lu、Haoyi Chen、Yuanhong Liu
DOI:10.1016/j.tet.2008.11.109
日期:2009.2
A highlyefficient Au-catalyzed cyclization of (Z)-enynols that proceeds under mild reaction conditions has been developed. This methodology provides rapid access to substituted furans and stereodefined (Z)-5-ylidene-2,5-dihydrofurans in a regioselective manner from suitably substituted (Z)-2-en-4-yn-1-ols.
New Synthetic Approach for the Construction of Multisubstituted 2-Acyl Furans by the IBX-Mediated Cascade Oxidation/Cyclization of<i>cis</i>-2-En-4-yn-1-ols (IBX=2-Iodoxybenzoic Acid)