The Vibrational Spectra of Pyridine and Pyridine-d5

Abstract

Pyridine‐d₅ has been prepared by exchange between pyridine vapor and heavy water in the presence of a palladium catalyst. Infrared and Raman spectra are reported for pyridine and pyridine‐d₅ over the spectral range 300–4000 cm⁻¹. Interpretation of the spectra with the help of the product rule and by analogy with the fundamental frequencies of benzene and benzene‐d₆ leads to complete sets of frequencies for the 27 vibrational degrees of freedom of pyridine and of pyridine‐d₅. The frequency assignment for pyridine does not differ greatly from previous ones, but is believed to be more reliable because of the additional spectroscopic data.