Photophysics and photochemistry of p-benzoylphenyldiphenylmethyl in solution

Free electron transfer mirrors rotational conformers of substituted aromatics: Reaction of benzyltrimethylsilanes with n-butyl chloride parent radical cations

“…1b). In light of these observations and spectral analogies to literature data concerning the benzyltrimethylsilane radical cation, 15 the short-lived transient was assigned to the radical cation 2e þ whereas the more stable species was interpreted as a p-benzoyltriphenylmethyl radical 16,17 2e derived from 2e þ by dissociation (2).…”

High intensity laser photochemistry of organic molecules in solution

“…It is interesting to note that there is a single, low-intensity reaction where just this type of carbene extrusion seems to have been observed in a related system, and the products from this reaction have been thoroughly characterized. 52 Neckers and coworkers have studied the photochemistry of the triarylmethyl radical 53 and isolated the products shown in Scheme 18. Thus, the observation of the 9-arylfluorene 54 and the triarylmethane 55 are unexceptional, but the other products, 56, 57, tetraphenylethylene, and benzophenone are precisely the products that one would expect from a carbene extrusion reaction as shown by the mechanism outlined in Scheme 18. It should be mentioned that deuterium labeling studies were conducted using benzene-dg. However, deuterium incorporation was only evaluated for 55.…”

Photochemistry of radicals and biradicals

“…The related (p-benzoylphenyl)diphenylmethyl radical has also been shown to undergo reversible photobleaching with the formation of hydrogen abstraction products, in addition to minor amounts of other materials which include 4-(9-fluorenyl)benzophenone. 35 Diphenylethyl and cyclopropylmethyl radicals have been reported to undergo efficient photobleaching in acetonitrile and to yield a transient at 480 nm similar to that obtained from triphenylmethyl radical.14 On this basis it was suggested that the chemistry involved a similar cyclization to that shown in reaction 11. Laserjet techniques have recently confirmed this hypothesis for the diphenylethyl radical produced by irradiation of a,a-diphenylpropiophenone.…”