both 1 and 2 possess ππ* nature strongly. Correspondingly, upon irradiation, 1 and 2 undergo photovalence isomerization to give the valene isomer of 1 and the Dewar isomer of 2, respectively. The interconversions between the naphthacenequinones and their valence isomers were reversible photochemically.
合成了7、8、9-三叔丁基-5,12-
萘并苯醌(1)和1,2,3-三叔丁基-5,12-
萘并苯醌(2)。1和2的最低激发单重态都强烈具有ππ*性质。相应地,在辐照下,1和2进行光价异构化,分别得到1的
戊烯异构体和2的杜瓦异构体。
萘并醌和它们的价异构体之间的相互转化在光
化学上是可逆的。