Abstract 4-R-Substituted-8-X-phenyl-3, 5, 10-trioxa-9-azabicyclo [3, 5, 0] dec-8-enes (X= H, 4-CH 3, 4-OCH 3, 4-Cl, 4-Br, 4-F, 3-NO 2, 3-Cl, 3-Br) have been prepared by cycloaddition of substituted benzenenitriloxides with 2-R-substituted 1, 3-dioxep-5-enes (R= H, CH 3, C 6 H 5). A mixture of the endo and exo adducts is formed, if R is CH 3 or C 6 H 5. Their irradiation produces high yields of the title compounds as the single products. High selectivity of the ...
