Hydrogen Bonding and Protonation Site in N,N‐Diethylnicotinamide

Abstract

Abstract The hydrogen bonded complexes between N,N‐diethylnicotinamide and proton donors such as phenol derivatives or hydrochlorid acid have been studied by infrared spectrometry. The thermodynamic parameters, the Δν OH values and the shift of the ν CO band to lower frequencies indicate that with phenol derivatives (pK a =10.2 ‐7.7 ), normal CO…HO hydrogen bonds are formed. The spectra show that the adduct with HCI is a proton transfer complex and that the protonation occurs at the nitrogen atom of the pyridine ring.