A convenient and general synthesis of trans-3-hydroxyflavanones from chalcones by dimethyldioxirane epoxidation and subsequent base-catalyzed cyclization
摘要:
2'-Hydroxychalcone epoxides were found to give trans-3-hydroxyflavanone and 2-(alpha-hydroxybenzyl)-3-coumaranone under basic conditions. Epoxidation of 2'-hydroxychalcones with dimethyldioxirane followed by treatment of tetrabutylammonium hydroxide provides a convenient and general method for the synthesis of trans-3-hydroxyflavanones.
The synthesis of α,β-epoxy-2′-hydroxychalcones (3-aryl-2,3-epoxy-1-(2-hydroxyaryl)propanones) 2 by direct epoxidation of (E)-2′-hydroxychalcones [(E)-3-aryl-1-(2-hydroxyaryl)propenone] 1 with dimethyldioxirane at subambient temperatures is reported. These acid- and base-sensitive epoxides, which have been hitherto difficult to prepare, were isolated in excellent yields and were completely characterized by spectral and microanalytical data. The now readily available 2′-hydroxy substituted chalcone oxides may serve as convenient precursors to flavonoid-type natural products.
A convenient and general synthesis of trans-3-hydroxyflavanones from chalcones by dimethyldioxirane epoxidation and subsequent base-catalyzed cyclization
作者:Tamás Patonay、Gábor Tóth、Waldemar Adam
DOI:10.1016/s0040-4039(00)60674-3
日期:1993.8
2'-Hydroxychalcone epoxides were found to give trans-3-hydroxyflavanone and 2-(alpha-hydroxybenzyl)-3-coumaranone under basic conditions. Epoxidation of 2'-hydroxychalcones with dimethyldioxirane followed by treatment of tetrabutylammonium hydroxide provides a convenient and general method for the synthesis of trans-3-hydroxyflavanones.