An electron paramagnetic resonance study of intermediates generated from aromatic aldiminesElectronic supplementary information (ESI) available: Gaussian98 or Jaguar optimised structures for precursor imines and imidoyl radicals together with their energies at all levels of theory. See http://www.rsc.org/suppdata/p2/b2/b201682f/
An electron paramagnetic resonance study of intermediates generated from aromatic aldiminesElectronic supplementary information (ESI) available: Gaussian98 or Jaguar optimised structures for precursor imines and imidoyl radicals together with their energies at all levels of theory. See http://www.rsc.org/suppdata/p2/b2/b201682f/
An electron paramagnetic resonance study of intermediates generated from aromatic aldiminesElectronic supplementary information (ESI) available: Gaussian98 or Jaguar optimised structures for precursor imines and imidoyl radicals together with their energies at all levels of theory. See http://www.rsc.org/suppdata/p2/b2/b201682f/
作者:Daniele Nanni、Patrizia Pareschi、John C. Walton
DOI:10.1039/b201682f
日期:2002.5.22
It was shown by EPR spectroscopy that N-aryl-imines undergo hydrogen atom abstraction by tert-butoxyl radicals to generate imidoyl radicals in competition with addition to the CN double bond to generate aminyl radicals. The latter were subsequently oxidised to nitroxides (aminoxyls) and also fragmented to release tert-butyl radicals and iminyl ethers. The main products identified were imines formed by combination of the imidoyl radicals with other radicals in the system. Thus, hydrogen abstraction is probably the most important homolytic pathway for the precursor imines. A similar reactivity pattern was found for N-tert-butyl-imines. DFT computations (B3LYP with a 6-31G* basis set) indicated that α-scissions of imidoyl radicals, ArNC˙R (R =
t-Bu or Me), to produce isonitriles, ArNC, were too endothermic to occur under the present experimental conditions. tert-Butoxyl radicals were
shown to add to 1-isocyano-4-chlorobenzene to generate N-arylimidoyl radicals that fragmented to afford 4-chloro-1-isocyanatobenzene.