dos Santos, Willian Henrique [UNESP]da Silva-Filho, Luiz Carlos [UNESP]2018-12-112018-12-112017-01-01Tetrahedron Letters, v. 58, n. 9, p. 894-897, 2017.1873-35810040-4039http://hdl.handle.net/11449/174148Chromeno[4,3-b]chromene derivatives were synthesized from multicomponent reaction between 4-hydroxycoumarin, aryl aldehyde derivatives and 1,3-cyclohexanedione promoted by niobium pentachloride. This new method is simple, cost-effective, provides good yields with good substrate generality and can be conducted in short reaction times.894-897engChromeneCoumarinLewis acidMulticomponent reactionsNiobium pentachlorideArtigo10.1016/j.tetlet.2017.01.062Acesso restrito2-s2.0-85010955739