Collect. Czech. Chem. Commun. 1987, 52, 1773-1779

Preparation and photochemistry of 3-cyanosubstituted condensed isoxazolines containing an oxygen atom

Vladimír Oremus, Lubor Fišera and Ladislav Štibrányi

Department of Organic Chemistry, Slovak Institute of Technology, 812 37 Bratislava


The 1,3-dipolar cycloaddition of cyanonitrile oxide to 2,3- and 2,5-dihydrofurane, 7-oxabicyclo[2,2,1]-2-heptene and derivatives of 1,3-dioxep-5-ene is described. The condensed isoxazolines Ia, IIIa, Va, Vc, Vd thus prepared are rearranged on irradiation into cyanosubstituted heterocyclic enaminoaldehydes IIa, IVa, VIa, VIc. The quantum yields of the photorearrangement of cyanoderivatives are higher than those of the phenyl derivatives, being within the limits from 0·068 to 0·19. The reaction of II with hydrazine gives the derivative IX of oxazino[4,5-d]pyridazine.