Pd-Catalyzed C–S Activation for [3 + 3] Annulation of 2-(Methylthio)benzofuran-3-carboxylates and 2-Hydroxyphenylboronic Acids: Synthesis of Coumestan Derivatives
摘要:
Pd-catalytic C-S activation was successfully applied to initiate the cross-coupling of (2-methylthio-3-ester)benzofurans with 2-hydroxyphenylboronic acids and sequential intramolecular transesterification process under Liebeskind-Srogl conditions. Thus, a novel [3 + 3] annulation strategy for efficient synthesis of coumestan derivatives has been developed from readily available starting materials.
Thirupathaiah; Venkateshwar Rao; Ramanna, Oriental Journal of Chemistry, 2010, vol. 26, # 4, p. 1521 - 1524
作者:Thirupathaiah、Venkateshwar Rao、Ramanna
DOI:——
日期:——
Efficient synthesis of 3-acyl-5-hydroxybenzofurans via copper(II) triflate-catalyzed cycloaddition of unactivated 1,4-benzoquinones with 1,3-dicarbonyl compounds
作者:Srinivasa Reddy Mothe、Dewi Susanti、Philip Wai Hong Chan
DOI:10.1016/j.tetlet.2010.02.066
日期:2010.4
A method to prepare a variety of substituted 3-acyl-5-hydroxybenzofurans efficiently that relies on copper(II) triflate-catalyzed cycloaddition of unactivated 1,4-benzoquinones with 1,3-dicarbonyl compounds is reported. The reaction was shown to be operationally straightforward and proceeds expediently under mild conditions to give the corresponding products in good to excellent yields (up to 95%) and with complete regioselectivity. (c) 2010 Elsevier Ltd. All rights reserved.