| Popis: |
Irradiation of 1, 1-diphenyl-2-(o-vinylphenyl)ethylene (3) leads stereoselectively to endo- 4, 5-diphenylbenzobicyclo[3.1.0]hex-2-ene (6) The analogous reaction of the homologous (o-propenylphenyl)ethyle derivative (4) seems to be less stereoselective, as products 10 and 11 could be isolated. In both cases a photodehydrocyclisation product (7 and 12, respectively) is also found. Possible mechanisms or the photocyclisation reactions are discussed, and the photochemical behaviour of 3 and 4 is compared with that of other o-vinylstilbenes, previously investigated. |
