DBU: a highly efficient catalyst for one-pot synthesis of substituted 3,4-dihydropyrano[3,2-c]chromenes, dihydropyrano[4,3-b]pyranes, 2-amino-4H-benzo[h]chromenes and 2-amino-4H benzo[g]chromenes in aqueous medium
作者:Jitender M. Khurana、Bhaskara Nand、Pooja Saluja
DOI:10.1016/j.tet.2010.05.082
日期:2010.7
We have reported DBU catalyzed one-pot synthesis of 3,4-dihydropyrano[3,2-c]chromenes, dihydropyrano[4,3-b]pyranes, 2-amino-4H-benzo[h]chromenes and 2-amino-4H-benzo[g]chromenes from aldehydes, active methylene compounds malononitrile/ethyl cyanocacetate, and 4-hydroxycoumarin/4-hydroxy-6-methylpyrone/1-naphthol/2-hydroxynaphthalene-1,4-dione in water under reflux. The attractive features of this process
我们已经报道了DBU催化一锅合成3,4-二氢吡喃并[3,2- c ]苯并二氢吡喃并[4,3- b ]吡喃,2-氨基-4 H-苯并[ h ]苯并二胺回流下得自醛,活性亚甲基化合物丙二腈/氰基乙酸乙酯和4-羟基香豆素/ 4-羟基-6-甲基吡喃酮/ 1-萘酚/ 2-羟基萘-1,4-二酮的-4 H-苯并[ g ]色酮。该方法的吸引人的特征是温和的反应条件,反应介质的可重复使用性,较短的反应时间,易于分离的产物以及优异的产率。