39153-79-2Relevant academic research and scientific papers
Efficient photodecarboxylation of trifluoromethyl-substituted phenylacetic and mandelic acids
Burns, Misty-Dawn,Lukeman, Matthew
, p. 821 - 826 (2010)
A total of eight CF3-substituted phenylacetic and mandelic acids are shown to undergo efficient photodecarboxylation (PDC; Φ = 0.37-0.74) in basic aqueous solution to give the corresponding trifluoromethyltoluenes or trifluoromethylbenzyl alcohols. The products are consistent with the almost exclusive formation of benzylic carbanions that subsequently react with water, with minor amounts (≤5%) of radical-derived products detected. Quenching studies indicate that the reaction likely proceeds from the singlet excited state. This work demonstrates that the CF3 group greatly facilitates the excited state ionic PDC of phenylacetic acids.
Gas-Phase Proton Transfer from Toluenes to Benzyl Anions
Han, Chau-Chung,Brauman, John I.
, p. 6491 - 6496 (2007/10/02)
Gas-phase proton-transfer kinetics of PhCH2(1-) + ArCH3 -> ArCH2(1-) + PhCH3 were studied for reactions having ΔH0rxn = 0 to -20 kcal/mol.These reactions are very slow in the absence of thermodynamic driving force; their reaction efficiencies range from 0.004 to 0.7.RRKM theory was applied to obtain energy differences between the proton-transfer transition state and the loose orbiting transition state from reaction efficiencies.Marcus theory provides a general model for a rate-equilibrium relationship with a constant intrinsic energy barrier of 7 kcal/mol forthe degenerate proton transfer from toluene to benzyl anion.The barrier is inferred from an RRKM fit to the energy difference of -5 kcal/mol between the proton-transfer transition state and the energy of the reactants and an estimated -12 kcal/mol for the energy of the collision complex relative to the reactants.In the reaction involving 3-nitrotoluene, electron transfer, which is some 11-12 kcal/mol less favorable than proton transfer, dominates almost exclusively.
