C-N vs. C-C Bond Photodissociation inN-(tert-butyldiphenylmethyl)aniline

Stylianos Garas, Michael G. Siskos, Antonios K. Zarkadis
2004 International Journal of Photoenergy  
The direct photolysis of the title aniline compoundPh2(Me3C)C-NHPh in acetonitrile with 248 nm laser light results in the dissociation of the C-N bond giving the corresponding (tert-Bu)diphenylmethyl radical1a•and the anilino radicalPhNH•detectable byns-laser flash photolysis (LFP) and ESR spectroscopy. The same radical1a•is also produced from the corresponding (tert-Bu)diphenylmethyl chloridePh2(Me3C)C-Cl either photolytically in MeCN through C-Cl bond homolysis or pulse radiolytically in THF;
more » ... the (tert-Bu)diphenylmethyl cation is also detected, however, at sorter time scales because of its high reactivity in the solvent MeCN. At higher laser pulse intensities the radical1a•is reexcited by a second photon leading through electrocyclization to the 4a,4b-dihydro-9-tert-butylfluorenyl radical (DHBF•) and finally to fluorenyl products. Product analyses of steady state photolyses using GC and GC-MS gave as principal products (tert-Bu)diphenylmethane, aniline and various 9-substituted fluorenyl derivatives, corroborating further the primary C-N bond cleavage and the formation of the radicals1a•andPhNH•. Other conceivable dissociation pathways leading to theC-CMe3or N-H bond rupture were not observed.
doi:10.1155/s1110662x04000303 fatcat:6pylxgm2pfeg3iwvonc7uehvui