【文章名】Synthesis of 12-Aryl-12H-benzo[i][1,3]-dioxolo[4,5-b]xanthene-6,11-diones Using Silica Sulfuric Acid as an Efficient and Versatile Catalyst under Solvent-Free Conditions
Synthesis of 12-Aryl-12H-benzo[i][1,3]-dioxolo[4,5-b]xanthene-6,11-diones Using Silica Sulfuric Acid as an Efficient and Versatile Catalyst under Solvent-Free Conditions
[摘要]：Some novel 12-aryl-12H-benzo[i][1,3]-dioxolo[4,5-b]xanthene-6,11-diones can be rapidly and efficiently synthesized in excellent yields by condensing a variety of aldehydes with 3,4-methylenedioxyphenol and 2-hydroxy-1,4-naphthoquinone in the presence of a catalytic amount of silica sulfuric acid under solvent-free conditions. The simple experimental procedure, solvent-free reaction conditions, utilization of an inexpensive and readily available catalyst, short period of conversion, and excellent yields are the advantages of the present method. Furthermore, the catalyst can be recycled and reused three times without significant loss of activity. The structures of the novel compounds are confirmed by IR, H-1-NMR, C-13-NMR, MS, and elemental analysis.
