Photodissociation at 193 nm of Cyclooctatetraene and Styrene into Benzene and Acetylene

Article abstract of DOI:10.1021/j100266a052

When irradiated in a molecular beam at 193 nm, both cyclooctatetraene and styrene dissociate into benzene and acetylene.The average kinetic energy release is 12percent of the available energy in both cases.So that the mechanism of the dissociation of styrene could be determined the ratio of mass 26 to mass 27 (C2H2/C2HD) was measured for C6H5CDCH2 and C6H5CHCH2 and found to be 1.46 +/- 0.10 and 2.29 +/- 0.10, respectively.These numbers rule out cyclooctatetraene as an intermediate in the dissociation of styrene.A bicyclo<4.2.0>octa-2,4,7-triene intermediate which can tautomerize by 1,3 hydrogen atom jumps in the smaller ring explains all the experimental results.