Photochemical reactions of stilbene

Fig. 13.11. A schematic drawing of the potential energy surfaces for the photochemical reactions of stilbene. Approximate branching ratios and quantum yields for the important processes are indicated. In this figure, the ground- and excited-state barrier heights are drawn to scale representing the best available values, as are the relative energies of the ground states of Z- and E -stilbene 4a,4b-dihydrophenanthrene (DHP). [Reproduced from R. J. Sension, S. T. Repinec, A. Z. Szarka, and R. M. Hochstrasser, J. Chem. Phys. 98 6291 (1993) by permission of the American Institute of Physics.]...

Miscellaneous Reactions. 1.2.1 Addition Reactions - A novel photochemical reaction of stilbene in carbon tetrachloride solution has been described. Irradiation of this system populates the first excited singlet state of stilbene which then abstracts a halogen from the solvent. The resulting radical pair composed of a trichloromethyl radical and (14) yields the products. 

Although earlier claimed to be unsuccessful, the photochemical reaction of stilbene with fumaric ester has now been used to synthesize p-truxinic acid (212). 

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