Abstract Cyclization–carbonylation–cyclizationcouplingreactions (CCC-coupling reactions) of N-propargylanilines and o-alkynylphenols catalyzed by (box)Pd(II) complexes afforded symmetrical bis(quinolin-3-yl) and bis(benzofuran-3-yl) ketones, respectively, in moderate to excellent yields. Cyclization–carbonylation–cyclizationcouplingreactions (CCC-coupling reactions) of N-propargylanilines and o-alkynylphenols
An efficient and ecofriendly method for the construction of 2,3-difunctionalized benzofuran derivatives in moderate to good yields from readily available 2-alkynylphenols has been developed. This tandem annulation process, featuring one pot, three steps, good functional group tolerance, and high atom economy, makes this transformation efficient and practical. Moreover, this protocol is scalable, illustrating its potential applications in synthetic and pharmaceutical chemistry.
Novel and Selective Palladium-Catalyzed Annulations of 2-Alkynylphenols To Form 2-Substituted 3-Halobenzo[<i>b</i>]furans
作者:Yun Liang、Shi Tang、Xu-Dong Zhang、Li-Qiu Mao、Ye-Xiang Xie、Jin-Heng Li
DOI:10.1021/ol060908f
日期:2006.7.1
[reaction: see text] A novel and selective palladium-catalyzed annulation of 2-alkynylphenols method for the synthesis of 2-substituted 3-halobenzo[b]furans is presented. In the presence of PdX(2), CuX(2), and HEt(3)NX, 2-substituted 3-halobenzo[b]furans were selectively obtained as the major products. The mechanism of the reaction was also discussed.