1338348-61-0Relevant academic research and scientific papers
Substituent effects on the reactions of aromatic triflones with para-X-anilines in methanol: Low intrinsic reactivity and transition state imbalances
El Guesmi, Nizar,Boubaker, Taoufik
supporting information; experimental part, p. 255 - 262 (2011/11/12)
A kinetic study is reported for SNAr reactions of 2,4,6-tris(trifluoromethanesulfonyl) anisole 1a with a series of para-X-substituted anilines 2a-e in a methanol solution at various temperatures. The substituent effects on free energy (δ≠G), enthalpy (δ≠H), and entropy (δ≠S) of activation are examined. Aniline addition to triflone 1a is characterized by a βX=0.57, αZ=0.31, and an imbalance of I = αZ-βX=-0.26. The imbalance shows that resonance development lags behind C-N bond formation at the transition state. Interestingly, analysis of the results in terms of Marcus theory reveals that these SNAr are associated with some extremely low intrinsic reactivity (log ko=-1.25
