The invention of radical reactions. 30. Diazirines as carbon radical traps. Mechanistic aspects and synthetic applications of a novel and efficient amination process

Article abstract of DOI:10.1021/ja00071a017

A number of diazirines were synthesized for the purpose of exploring the addition of a carbon radical to the nitrogen-nitrogen double bond. Carbon radicals, generated from the photolysis of the O-acyl derivatives of N-hydroxy-2-thiopyridone or via radical exchange from the corresponding organotellurides, were shown to add smoothly to the diazirines leading to imines 34. When 3-(trifluoromethyl)-3-phenyldiazirine (13) is used as the trap, the thus formed imines can be easily hydrolyzed to amines. A mechanism that involves dimerization of the diaziridinyl radicals 32 to produce tetraazo intermediates 33 is suggested in accord with variable temperature NMR data for the reaction. Proof for this mechanistic scheme was furthermore obtained by isolation and X-ray structure determination of 33d. The first X-ray structure of a 3-(trifluoromethyl)-3-aryldiazirine is also reported.