Externally sensitized mesolytic fragmentations in dithiane–ketone adducts
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چکیده
The apparent activation enthalpies, DH, for externally sensitized mesolytic fragmentations in benzophenone–dithiane adducts were obtained in variable temperature photolyses and compared with DFT activation barriers calculated for b-scission in the corresponding oxygen-centered radicals. The results of these experimental and theoretical studies further support the mechanism in which deprotonation of the hydroxy-group, in the transient cation radical, is coupled with intramolecular electron transfer furnishing the O-centered radical, which subsequently fragments. The quantum yields of fragmentation increase for higher alkyl substituted dithiane adducts. 2006 Elsevier Ltd. All rights reserved.
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تاریخ انتشار 2006