An efficient and environmentally benign protocol for the synthesis of dibenzo [b,i]xanthene-tetraones and fluorescent hydroxyl naphthalene-1,4-diones in the presence of a catalytic amount of ZrOCl2·8H2O as an inexpensive and eco-friendly catalyst with high catalytic activity under solvent-free conditions is reported.
Phosphoric acid supported on alumina (H3PO4/Al2O3) is an efficient catalyst for the catalytic multi-component condensation reaction and a wide variety of syntheses of benzoxanthene pigments in good yields. The remarkable features of this new procedure are high conversions, shorter reaction times, cleaner reaction, and simple experimental and work-up procedures.
Graphene Oxide Incorporated Strontium Nanoparticles as a Highly Efficient and Green Acid Catalyst for One-Pot Synthesis of Tetramethyl-9-aryl-hexahydroxanthenes and 13-Aryl-5H-dibenzo[b,i]xanthene-5,7,12,14(13H)-tetraones Under Solvent-Free Conditions
applying graphene oxide/strontium as a nanocatalyst for xanthene derivativessynthesis. The key potential benefits of the present method are including high yields, short reaction time, easy workup, recyclability of catalyst and ability to tolerate a variety of functional groups which gives economical as well as ecological rewards. The nanocatalyst easily separated from the reaction mixture easily by
Trityl bromide versus nano-magnetic catalyst in the synthesis of henna-based xanthenes and bis-coumarins
作者:Mahmoud Zarei、Mohammad Ali Zolfigol、Ahmad Reza Moosavi-Zare、Ehsan Noroozizadeh
DOI:10.1007/s13738-017-1155-4
日期:2017.10
trityl bromide (TrBr) as a new, efficient, mild and neutral catalyst was used for the synthesis of henna-based xanthenes (aryl-5H-dibenzo[b,i]xanthene-5,7,12,14(13H)-tetraones) and bis-coumarins by in situ generation of trityl carbocation undersolvent-freeconditions in comparison with [Fe3O4@SiO2@(CH2)3-Im-SO3H]Cl as an acidic and reusablecatalyst for the first time. Graphical Abstract
A simple procedure for the synthesis of benzoxanthene derivatives under microwave irradiation conditions
作者:Yan Chen、Shanshan Wu、Shujiang Tu、Chunmei Li、Feng Shi
DOI:10.1002/jhet.5570450345
日期:2008.5
A rapid and efficient method is developed to synthesize a series of benzoxanthenederivatives by the reaction of aldehydes and 2-hydroxynaphthalene-1,4-dione in mixed solvent of acetic acid and ethylene glycol undermicrowaveirradiation. The method has the advantages of short synthetic route, operational simplicity and higher yields (70%∼85%).