A FACILE ROUTE TO 5-ALKYL-2(3H)-FURANONES BY PHOTOISOMERISATION OF ENEDICARBONYL COMPOUNDS

Article abstract of DOI:10.1016/0040-4020(82)80143-9

A new and useful synthesis of a title compounds is reported.They can be obtained easily by photocyclization of enedicarbonyl compounds 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.