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
Enantioselective Copper-Catalyzed Alkynylation of Benzopyranyl Oxocarbenium Ions
作者:Harathi D. Srinivas、Prantik Maity、Glenn P. A. Yap、Mary P. Watson
DOI:10.1021/acs.joc.5b00364
日期:2015.4.17
We have developed highly enantioselective, copper-catalyzedalkynylations of benzopyranyl acetals. By using a copper(I) catalyst equipped with a chiral bis(oxazoline) ligand, high yields and enantioselectivities are achieved in the alkynylation of widely available, racemic isochroman and chromene acetals to deliver α-chiral oxygen heterocycles. This method demonstrates that chiral organometallic nucleophiles
Transition-Metal-Free Cross-Coupling of Indium Organometallics with Chromene and Isochroman Acetals Mediated by BF<sub>3</sub>·OEt<sub>2</sub>
作者:José M. Gil-Negrete、José Pérez Sestelo、Luis A. Sarandeses
DOI:10.1021/acs.orglett.6b02058
日期:2016.9.2
coupling of triorganoindiumreagents with benzopyranyl acetals mediated by a Lewis acid has been developed. The reaction of R3In with chromene and isochroman acetals in the presence of BF3·OEt2 afforded 2-substituted chromenes and 1-substituted isochromans, respectively, in good yields. The reactions proceed with a variety of triorganoindiumreagents (aryl, heteroaryl, alkynyl, alkenyl, alkyl) using