1. 2-[2-(2vinylphenyl)ethenyl]thiophene ( 30 ) and 2,2-(o-phenylenedivinylene)dithiophene ( 31 ) were studied under pyrolytic and photolytic conditions, photolytic of 30 gave upon bicyclic product 35, whereas photolytic of 31 gave products 37 and 39, FVP of 30 and 31 gave 34 and 37, respectively,which all include naphthalene nucleus. 2. 2-methoxystilbene ( 17 ) and 3-methoxystilbene ( 18 ) were studied under pyrolytic conditions, FVP of 17 gave single product 2-Phenylbenzo[b]furan ( 23 ), FVP of 18 gave 2-phenanthrol ( 27 ), ( 4-phenanthrol ) ( 28 ), trans-3- hydroxystilbene ( 29 ), Fluoren 9 -one ( 30 ) and a pair of isomer 1H-benz[e]indene ( 11a ) and 3H-benz[e]indene (11b).