The photochemistry of 5-phenyl-, 5-(2', 5'-dimethoxyphenyl)-, 5-(2'-acetoxy-5'- methoxyphenyl)-and 5-(2', 5'-diacetoxyphenyl)-2 (3H)-furanone (1a-d) has been investigated. Compound 1a yields phenyl vinyl ketone as expected. Similarly, 1b affords the corresponding aryl vinyl ketone but, in this case, photodimerization also occurs. Irradiation of the two o-acetoxyaryl furanones 1c and 1d gives rise to the formation of chromones as the ...
