Phenylfluorenyl dimer

In weaker acid systems, other reactions involving the triplet state supervene to the exclusion of dimerization. Photolysis of 85 in 3-3% sulfuric acid, 96-5% acetic acid, and 0-2% water gave as products tri-phenylmethane (93), 9-phenylfluorene (94), 6is-9-phenylfluorenyl peroxide (95) and benzophenone (96). When benzene was present, tetra-phenylmethane (97) was also formed in addition to the other products. When the triphenylmethyl cation is irradiated in 3-3% H2SO4, 80 1% HOAc, 16-4% toluene, and 0-2% H2O, the products observed were... 

Thermal dimerization of 2,3,5,6-tetrachloro-p-phenylenediimine 351 A remarkable benzidine rearrangement 352 Condensation of aromatic perchloroamines 353 Perchlorinated organic radicals and related intermediates 354 Perchlorobenzyl radicals 354 Perchlorodiphenylmethyl radicals 355 Perchlorotriphenylmethyi radicals 361 Perchloro-9-phenylfluorenyl radicals and related species 384 Inert perchloro-aza-radicals 389 Perchloro-p-quinodimethanes, perchloro-/ -xylylenes and related compounds 390... 

The cyclization of the triphenylmethyl radical under the influence of light, giving bi(9-phenylfluorenyl), a dimer of the 9-phenylfluorenyl radical, was studied early this century (Gomberg and Cone, 1904 Schmidlin and Garcia-Banus, 1912). 

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