RATES OF DEPROTONATION OF (4-NITROPHENYL)ACETONITRILE AND (2-4-DINITROPHENYL)ACETONITRILE IN 50% Me2SO--50% WATER.

Article abstract of DOI:10.1021/ja00351a037

Rates of reversible deprotonation of (2,4-dinitrophenyl)acetonitrile (2-(NO//2)//2) by OH** minus , water, piperidine, morpholine, cacodylate, acetate, formate, and chloroacetate ion and of (4-nitrophenyl)acetonitrile (2-NO//2) by OH** minus , piperidine, morpholine, n-butylamine, and 2-methoxyethylamine in 50% Me//2SO-50% water at 20 degree C are reported. The intrinsic rate constant (in the Marcus sense) for the dinitro derivative is about 10-fold lower than that for the mononitro compound. This is consistent with the stronger charge delocalization in the anion of the dinitro compound, which leads to greater structural/electronic/solvational reorganization during the reaction. Bronsted beta //B values (variation of base) for the deprotonation by piperidine and morpholine are 0. 50 for 2-(NO//2)//2 and 0. 74 for 2-NO//2, respectively. Bronsted alpha //C//H values (variation of C-H acid) are 0. 47 for deprotonation by morpholine and 0. 35 for deprotonation by piperidine.