STUDIES ON SOLID-STATE PHOTOREACTION OF A CETYLCOUMARIN AND ITS DERIVATIVES WITH INDOLE

The photochemical reaction of 3-acetylcoumarin and its 7-acetyloxy, 7- benzoyloxy, 6-bromo and 5,6-benzo derivatives with indole in solid sta te gave only condensation products, while 3-acetyl-6-nitrocoumarin wit h indole gave ring-cleavage decarbonyl addition product in the solid s tate, 3-Acetylcoumarin and its derivatives with indole can not undergo photochemical reaction in solution, The solid-state photochemical rea ction shows a high selectivity. The effect of the nature of substituen t and the position of substitution were also investigated, the withdra wing substituent facilitate the photoreaction and there is a higher re activity of acetyl at position 3 than at position 6 and 8. The structu res of six new products were identified by IR, MS, H-1 NMR and element al analysis.