Practical and Highly Selective CH Functionalization of Structurally Diverse Ethers
作者:Miao Wan、Zhilin Meng、Hongxiang Lou、Lei Liu
DOI:10.1002/anie.201407083
日期:2014.12.8
A trityl ion mediated CHfunctionalization of ethers with a wide range of nucleophiles at ambient temperature has been developed. The reaction displays high chemoselectivity and good functional group tolerance. The protocol also exhibits excellent regio‐ and diastereoselectivities for the unsymmetric ethers, thus stereoselectively generating highlyfunctionalized disubstituted 2,5‐trans tetrahydrofurans
Strategic use of oxophilic (hard) gold(III) and π-philic (soft) gold(I) catalysts provides access to two types of cyclic ethers from propargylic alcohols. Thus, heating propargylic alcohols with an oxophilic gold(III) catalyst (AuBr3) results in cyclization to afford cyclic ethers bearing an acetylenic moiety, due to coordination of gold(III) to the oxygen of the propargylic hydroxyl group. On the
An economic and practical transformation from secondary alkyl-substituted propargyl acetates to a variety of nucleophilic substitution products was described. This reaction was catalyzed by inexpensive InCl3. High yields and excellent chemoselectivity were obtained. The five-, six-, and seven-membered propargyl cycloethers were also successfully constructed by this protocol.