PHOTOCHEMISTRY SYNTHESIS AND CHARACTERIZATION OF BENZOCYCLOHEPTAN-1,5-DIONE DERIVATIVES

Some new benzocycloheptan-1,5-diones derivatives I (3: R = t-Bu, R' = H; 4: R = Ph, R' = H; 5: R = PhCOCH(2), R' = H; 6: R = CH3COCH2, R' = H; 7 : R = t-Bu, R' = ethenyle and 8 : R = Ph, R' = ethenyle) were syn thetized through photocycloaddition of 2-acylindan-1,3-diones 2 with s tyrene and paradivinylbenzene (pDVB) respectively. The reaction procee ds regioselectively at the endocyclic enol. This regioselectivity was not observed on the linear beta-triketones, previously reported [1]. T he formation of a double addition product -(2,2-dimethylpropionyl)-ben zocycloheptyl)-benzene 9 shows how a network could be formed if these 2-acylindan-1,3-diones 2 moities are graft in side chains of macromole cules. The enolic equilibrium of the obtained benzocycloheptan-1,5-dio nes derivatives, are discussed. Every products were characterized by m eans of elemental analysis and IR, UV, H-1 and C-13 NMR spectroscopies .