Diaziridinones, 1, undergo oxidation-reduction and rearrangement reactions in the presence of substituted hydrazines. Reaction of di-t-butyldiaziridinone, 1a, with 1,2-di-t-butylhydrazine, 2a, affords 1,3-di-t-butylurea and azobis-2-methyl-2-propane (major products), t-(t-butylcarbamyl)-2,2-dimethylaziridine, 3a (i.e., N-t-butyl-2,2-dimethylaziridinecarboxamide), in 20% yield, and a few per cent of di-t-butylcarbodiimide. In the reaction of di-t-butyldiaziridinone, 1a, with 1,2-di-t-amylhydrazine, 2b, and of di-t-amyldiaziridinone, lb, with 1,2-di-(-butylhydrazine, 2a, azo product comes from hydrazo reactant, excluding an addition-fragmentation mechanism (Scheme I), and supporting a hydrogen-transfer mechanism for the reduction of diaziridinone to the urea. The rearrangement reaction, 1 → 3, is favored by increasing lability of hydrogen β to nitrogen in the diaziridinone: 1b and 2a afford 1-(-amylcarbamyl)-2,2,3-trimethylaziridine (77%) and the urea (7%); di-2-methyl-3-phenyl-2-propyl)diaziridinone, 1c, and 2a afford 99% 1-(2-methyl-3-phenyl-2-propylcarbamyl)-2,2-dimethyl-3-phenylaziridine, 3c. N-t-Butyl-Nʹ-(2-methyl-3-phenyl-2-propyl)diaziridinone and 2a afford the corresponding urea (50%) and 1-(t-butylcarbamyl)-2,2-dimethyl-3-phenylaziridine, 3d (50%). In the absence of the hydrazines, the diaziridinones are stable under the reaction conditions in the presence or absence of products, indicating that the hydrazines are true catalysts for the rearrangement reaction. Low hydrazine concentrations favor rearrangement reaction over reduction of diaziridinone. A decrease in either the size or the number of substituents on the hydrazine increases the rate of reaction and decreases the aziridinecarbox-amide/urea ratio; even lc goes largely to the urea in the presence of 1,2-dimethylhydrazine. Tetramethyl-hydrazine is ineffective with la and 1b, but effects the isomerization of 1c → 3c (at a substantially slower rate than di-(-butylhydrazine). The results are discussed (eq 4-8) in terms of initial hydrogen atom transfer to oxygen of diaziridinone with N-N cleavage. Intermolecular transfer of a second hydrogen to this species loads to the urea; intramolecular hydrogen abstraction (6-center) followed by cyclization leads to an azacyclo-propylcarbinyl radical, convertible into rearrangement product 3 by hydrogen atom transfer to an acceptor. © 1969, American Chemical Society. All rights reserved.
