Photochemistry of Host-Guest Complex.III. Effect of Guest Cation on the Photoreactivity of Acetophenone Oxime Derivatives Having Crown Ether Moiety

Article abstract of DOI:10.1246/bcsj.53.2304

The syn-anti isomerisation of acetylbenzocrown ether oximes was stimulated by the complex-formation with sodium ion.The photolysis of these oximes gave mother ketones and amides through an oxaziridine intermediate.The photolysis of the oximes was depressed by the formation of host-guest complexes.Reactivity in the photolysis of the crown ether oximes corresponds to that 3,4-dimethoxyacetophenone oxime, whereas the reactivity of the complexed crown ether oxime with sodium ion corresponds to that of p-cyanoacetophenone oxime.Such behavior is explained by the change of the electronic properties of excited states of acetophenone oxime chromophore, which enhances the intersystem crossing.