TFA-mediated tandem Friedel-Crafts alkylation/cyclization/hydrogen transfer process for the synthesis of flavylium compounds.
The tandem reaction of phenols and chalcones in refluxing TFA gave the flavylium species of 2-hydroxy-2-phenyl-2H-chromenes in moderate to good isolated yields. The reaction was proposed to involve a tandem transformation of Friedel-Crafts alkylation, dehydrative cyclization, intermolecular hydrogen transfer, and hydration. As a multifunctional catalyst, TFA mediated the processes efficiently and cleanly.
Wu
Yan-Chao
YC
Beijing National Laboratory for Molecular Science (BNLMS), Center for Chemical Biology, Institute of Chemistry, Chinese Academy of Sciences, Beijing, PR China.
Liu
Li
L
Liu
Yu-Liang
YL
Wang
Dong
D
Chen
Yong-Jun
YJ
D000478:Alkylation; D000872:Anthocyanins / Q000138:chemical synthesis*; D003500:Cyclization; D005419:Flavonoids / Q000138:chemical synthesis*; D006859:Hydrogen / Q000737:chemistry*; D008956:Models, Chemical; D014269:Trifluoroacetic Acid / Q000737:chemistry*
D000872:Anthocyanins; D005419:Flavonoids; D006859:Hydrogen; D014269:Trifluoroacetic Acid