Silica Supported Zr(HSO<sub>4</sub>)<sub>4</sub> Catalyzed Solvent-free Synthesis of [1]Benzopyrano[ 4,3-b][1]benzopyran-6-ones and Xanthenones
作者:Shahrzad Abdolmohammadi
DOI:10.2174/1570178610666131212231709
日期:2014.4
A clean and efficient procedure is described for the synthesis of 7-(4-hydroxy-2-oxo-2H-1-benzopyran-3-yl)-
6H,7H-[1]benzopyrano[4,3-b][1]benzopyran-6-ones and 2-(2,3,4,9-tetrahydro-3,3-dimethyl-1-oxo-1H-xanthen-9-yl)-3-
hydroxy-5,5-dimethyl-2-cyclohexen-1-ones from a quasi-Knoevenagel-Michael reaction sequence of salicylaldehydes
with compounds having active methylene groups [4-hydroxycoumarin (4-hydroxy-2H-1-benzopyran-2-one) and dimedone
(5,5-dimethyl-1,3-cyclohexanedione)] in a ratio of 1:2, in the presence of a catalytic amount of 60% Zr(HSO4)4/SiO2
as an efficient heterogeneous catalyst at 60 °C and under solvent-free conditions.
描述了一种清洁高效的合成步骤,用于合成7-(4-羟基-2-氧代-2H-1-苯并吡喃-3-基)-6H,7H-[1]苯并吡喃[4,3-b][1]苯并吡喃-6-酮和2-(2,3,4,9-四氢-3,3-二甲基-1-氧代-1H-萘烷-9-基)-3-羟基-5,5-二甲基-2-环己烯-1-酮。这些化合物是通过将水杨醛与具有活性亚甲基基团的化合物(4-羟基香豆素(4-羟基-2H-1-苯并吡喃-2-酮)和二美酮(5,5-二甲基-1,3-环己烯二酮))按1:2的比例进行准Knoevenagel-Michael反应序列合成的,反应在60 °C下进行,并使用60% Zr(HSO4)4/SiO2作为高效的异相催化剂,且不使用溶剂。