title: Electronic effects in the N-nitrosation of N-benzylpivalamides.
abstract: A series of N-4-R-benzylpivalamides (R = MeO, Me, H, CF(3), and NO(2)) was nitrosated using a standardized solution of N(2)O(4) in CDCl(3) at -40 degrees C. The reactions, which produced the corresponding N-4-R-benzyl-N-nitrosopivalamides, were followed by (1)H NMR spectroscopy. The rate of nitrosation was found to vary in a systematic way with the nature of the 4-R-group on the aromatic ring. Thus, electron-releasing groups increased the rate of the reaction, whereas electron-withdrawing ones decelerated N-nitrosation. In a similar fashion, the nitrosations were accelerated in polar solvents but were slower in solvents of low polarity. The sensitivities of N-nitrosation to these intra- and intermolecular electronic effects are compared to those from a previous study examining the dependence of the kinetics of nitrosoamide thermolyses on the same factors.
authors.affiliation: Department of Chemistry, McNeese State University, Lake Charles, Louisiana 70609, USA. rdarbeau@mail.mcneese.edu
authors.forename: Ron W
authors.initials: RW
authors.lastname: Darbeau
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Pease
authors.forename: Edson V
authors.initials: EV
authors.lastname: Perez