A facile route to 5-alkyl-2(3H)-furanones by photoisomerisation of enedicarbonyl compounds
作者:M. D'Auria、A. De Mico、G. Piancatelli、A. Scettri
DOI:10.1016/0040-4020(82)80143-9
日期:1982.1
A new and useful synthesis of a title compounds is reported. They can be obtained easily by photocyclization of enedicarbonylcompounds 3 and 4. A different behaviour, ascribed to the geometry of a double bond, is observed; 3 are converted only to butenolides 5, while trans-isomers 4 are converted into alkyl-furyl-ketones 5 and 6. A possible mechanism is described.
2-acylfuran derivatives
(R: alkyl, phenyl, etc.; R1: H, alkyl) are prepared in high yield by reaction, in the presence of a boron trifluoride complex catalyst, of a furan compound
with
CHXY (X: H, Cl, Br; Y: Cl, Br) or with RCOOH in the presence of (XYCHCO)20.