The effect of substituents on the rate of pyramidal inversion of 1-aryl-2,2-dimethylaziridines
Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review
Author(s)
Related Research Unit(s)
Detail(s)
Original language | English |
---|---|
Pages (from-to) | 4050-4056 |
Journal / Publication | Journal of the American Chemical Society |
Volume | 92 |
Issue number | 13 |
Publication status | Published - 1970 |
Link(s)
Abstract
The influence of electronic effects on the barrier to pyramidal inversion in meta- and para-substituted N-phenyl-2,2-dimethylaziridines has been investigated by an examination of the temperature-dependent nmr spectrum. Rate constants and free energies of activation at the coalescence temperature have been determined. The inversion barrier shows a linear correlation with the Hammett substituent constant σ-(ρ = 2.8-3.3 at -60°). The direction of the substituent effect parallels that previously found for pyramidal inversion at sulfur in sulfoxides and at phosphorus in phosphines, but the magnitude of the effect is greatest in the aziridines. These results are ascribed to conjugation of the lone pair on the inverting center with the attached arene π system, an effect which is more pronounced for first- than for second-row elements, and which finds its maximum expression in the transition state for the inversion process.
Citation Format(s)
The effect of substituents on the rate of pyramidal inversion of 1-aryl-2,2-dimethylaziridines. / Andose, Joseph D.; Lehn, Jean-Marie; Mislow, Kurt et al.
In: Journal of the American Chemical Society, Vol. 92, No. 13, 1970, p. 4050-4056.
In: Journal of the American Chemical Society, Vol. 92, No. 13, 1970, p. 4050-4056.
Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review