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
5-苯基-,5-(2',5'-二
甲氧基苯基)-,5-(2'-乙酰氧基-5'-
甲氧基苯基)-和5-(2',5'-
二乙酰氧基苯基)-2(研究了3H)-
呋喃酮(1a-d)。化合物1a如预期产生
苯乙烯基酮。类似地,1b提供相应的芳基
乙烯基酮,但是在这种情况下,也会发生光二聚化。辐照两个邻-乙酰氧基芳基
呋喃酮1c和1d导致形成
色酮作为主要产物。这个有趣的结果可以用内酯环的光
化学开环,然后自由基加成到乙酰氧基上来解释。