A simple, convenient, and one-pot synthesis of angularly fused [6-7-5], [6-7-6], [6-7-7], and [6,7] carbocyclic ring systems from Baylis-Hillman acetates through a strategy involving alkylation, formation of a vinyl chloride, and intramolecular cyclization (Friedel-Crafts or Michael reaction) is described.
An efficient synthesis of 3-arylmethyl-7,8-dihydro-6H-chromene-2,5-diones from Baylis–Hillman adduct acetates under solvent-free conditions
作者:Weihui Zhong、Yongzhi Zhao、Weike Su
DOI:10.1016/j.tet.2008.04.003
日期:2008.6
A simple, efficient synthesis of 3-arylmethyl-7,8-dihydro-6H-chromene-2,5-dione 4 from Baylis-Hillman adduct acetates derived from aromatic aldehydes and cyclohexane-1,3-diones under solvent-free conditions is described. Interestingly, when Baylis-Hillman adducts derived from aliphatic aldehydes were tested under the similar conditions, the unexpected stereoisomers 5 and 6 were obtained in moderate yields. A plausible mechanism for the formation of 4-6 is proposed. (C) 2008 Elsevier Ltd. All rights reserved.