Extended Grunwald-Winstein Analysis - LFER Used to Gauge Solvent Effects in p-Nitrophenyl Chloroformate Solvolysis

International Journal of Molecular Sciences

关键词: Solvolysis;    addition-elimination;    association-dissociation;    p-nitrophenyl chloroformate;    chloroformates;    Grunwald-Winstein equation;    LFERS;    leaving group effects;   

DOI  :  10.3390/ijms9112231

来源: DOAJ

【 摘 要 】

Specific rates of solvolysis at 25oC for p-nitrophenyl chloroformate (1) are analyzed using the extended (two-term) Grunwald-Winstein equation. For 39 solvents, the sensitivities (l = 1.68±0.06 and m = 0.46±0.04) towards changes in solvent nucleophilicity (l) and solvent ionizing power (m) obtained, are similar to those previously observed for phenyl chloroformate (2) and p-methoxyphenyl chloroformate (3). The observations incorporating new kinetic data in several fluoroalcohol-containing mixtures, are rationalized in terms of the reaction being sensitive to substituent effects and the mechanism of reaction involving the addition (association) step of an additionelimination (association-dissociation) pathway being rate-determining. The l/m ratios obtained for 1, 2, and 3, are also compared to the previously published l/m ratios for benzyl chloroformate (4) and p-nitrobenzyl chloroformate (5).

【 授权许可】

Unknown