摘要:
[GRAPHICS]Direct photolysis of p-RO(R = alkyl or aryl)-2-styrylfurans (1a-f), 2-styrylthiophenes (2a-f), and 2-styryl-N-methylpyrrole (3) in hydrated dichloromethane gives 5-(3-oxo-1-butenyl)benzo[b]furan (4), -thiophene (5), and N-methylpyrrole (6), respectively, in good isolated yields, However, photolysis of 1a,b,e and 2a,b,e in dehydrated benzene gives 5-(3-RO-1,3-butadienyl)benzo[b]furans (7a,b,e) and thiophenes (8a,b,e) in good yields, Photolysis of 7 and 8 in hydrated dichloromethane produces 4 and 5, respectively.