Synthesis of 3-aryl-4-chalcogen-2H-benzopyrans from 3-iodo-4-chalcogen-2H-benzopyrans using a Suzuki cross-coupling
作者:Benhur Godoi、José S.S. Neto、Adriane Sperança、Carmine Ines Acker、Cristina W. Nogueira、Gilson Zeni
DOI:10.1016/j.tetlet.2009.07.008
日期:2009.9
The Suzuki cross-coupling reaction of 3-iodo-4-chalcogen-2H-benzopyran derivatives with a variety of organoboron compounds in the presence of catalytic amount of palladium salt is described. This cross-coupling reaction proceeded cleanly and was performed with aryl boronic acids bearing electron-withdrawing, electron-donating, and neutral substituents, furnishing the corresponding products in moderate to good yields. (C) 2009 Elsevier Ltd. All rights reserved.
Synthesis of Organochalcogen Propargyl Aryl Ethers and Their Application in the Electrophilic Cyclization Reaction: An Efficient Preparation of 3-Halo-4-Chalcogen-2<i>H</i>-Benzopyrans
作者:Benhur Godoi、Adriane Sperança、Davi F. Back、Ricardo Brandão、Cristina W. Nogueira、Gilson Zeni
DOI:10.1021/jo900307k
日期:2009.5.1
atom of the electrophilic chalcogen species. Additional versatility in this process was demonstrated with respect to a diverse array of functionality in the aromatic ring at propargyl aryl ethers. These propargyl aryl ethers, bearing the chalcogen group, underwent highly selective intramolecular cyclizations when treated with I2 or ICl affording 3-iodo-4-chalcogen-2H-benzopyrans. The results demonstrated