New method for the synthesis of chromeno[4,3-b]chromene derivatives via multicomponent reaction promoted by niobium pentachloride
作者:Willian Henrique dos Santos、Luiz Carlos da Silva-Filho
DOI:10.1016/j.tetlet.2017.01.062
日期:2017.3
Chromeno[4,3-b]chromene derivatives were synthesized from multicomponentreaction between 4-hydroxycoumarin, aryl aldehyde derivatives and 1,3-cyclohexanedione promoted by niobiumpentachloride. This new method is simple, cost-effective, provides good yields with good substrate generality and can be conducted in short reaction times.
Catalytic Method for Synthesis of Benzopyrano[3,2-c]chromene-6,8-dione Derivatives by Heteropoly Acids
作者:Radineh Motamedi、Saeede Baghbani、Fatemeh F. Bamoharram
DOI:10.1080/00397911.2010.542536
日期:2012.6
Benzopyrano[3,2-c]chromene-6,8-dione derivatives were prepared by a three-component one-pot cyclocondensation of 4-hyroxycoumarin, aldehydes, and 1,3, cyclohexadione using a catalytic amount of heteropolyacids in boiling ethanol in very good yields and rates.