Alkylation of 1,3-dicarbonyl compounds with benzylic and propargylic alcohols using Ir–Sn bimetallic catalyst: synthesis of fully decorated furans and pyrroles
作者:Paresh Nath Chatterjee、Sujit Roy
DOI:10.1016/j.tet.2011.04.092
日期:2011.6
The heterobimetallic complex [Ir(COD)(SnCl3)Cl(μ-Cl)]2 catalyzes the direct substitution of hydroxyl groups in benzylic and propargylicalcohols by 1,3-dicarbonyl moiety. In 4-hydroxycoumarin, benzylation and propargylation occurs at the 3-position. Selective propargylation or allenylation takes place depending on the nature of propargylicalcohol. By applying the methodology, multi-substituted furans
An efficient and simple method for the oxidative coupling of benzylic and allylic sp(3) C-H bonds with active methylenic sp(3) C-H bonds under metal-free conditions was developed by employing 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) as an oxidant. The reaction was shown to proceed smoothly for various 1,3-dicarbonyl compounds with a range of benzylic and allylic substrates in good to excellent yields. (C) 2010 Elsevier Ltd. All rights reserved.