Photolysis phenyl anilides

Azetidinones are also formed on photolysis of cis-a-phenyl-cinnamanilide (361), but in addition a small quantity of a cis-trans mixture of 3,4-diphenyl-3,4-dihydroquinolin-2-one (362) was obtained. The yield of quinolinone was considerably increased in the photocyclization of alkyl-substituted acrylanilides.389 The anilide (363) of tiglic acid, for example, was converted into the anilide (364) of angelic acid by photochemical cis-trans isomerism, and into a mixture of cis- and [Pg.103]

However, in a systematic study of a series of unsubstituted and m-substituted phenyl-esters and anilides in solution in the presence of tenfold molar excess / -CD, Ramamurthy and co-workers [265,270] obtained remarkable o-selectivity. Some of their results are reported in Table 6. In the case of m-substituted derivatives, one of the two ortho rearranged products was preferentially formed. Table 7. It was concluded that both the decreased extent of the reaction from the free substrate and a tight fit between the host and the guest are of major importance. When the photolysis was carried out in the solid complexes, the selectivity effects were obtained to a much greater extent than in solution. In these conditions, the absence of complexation equilibrium, whose dynamic nature can allow the radical intermediates to escape and/or reorient before recombining, and the tight molecular packing are key factors [270]. 

TABLE 6 Product Distribution (%) upon Photolysis of Phenyl Esters and Anilides under Various Conditions ... 

---