Asymmetric double proton transfer of excited 1 : 1 7-azaindole/alcohol complexes with anomalously large and temperature-independent kinetic isotope effects
Bridging alcohols, tunneling protons: The intrinsic proton-transfer dynamics of cyclic H-bonded 1:1 7-azaindole/alcohol complexes in n-alkanes has been investigated at the lowest-lying excited singlet state with variation of alcohol, solvent, isotope, and temperature by using static and time-resolved spectroscopy. The proton transfer occurs asymmetrically, and the rate is governed by tunneling although it is assisted by heavy-atom motions.