The vibrational spectra, molecular structure and conformation of organic azides

Matrix-isolation FTIR study of azidoacetone and azidoacetonitrile

“…Marcin Frankowski et al Table 3: i) weak bands around 2500 cm -1 and in the range of 2900-4500 cm -1 as well as matrix isolated water and CO 2 bands regions have been omitted; ii) frequencies grouped in braces show fine structure of the bands; mmedium, s -strong, vs -very strong, the others are weak or very weak; b -broad. # Underlined frequencies for AzN/N 2 relate to previous assignment [6]. The three weak to moderately intense bands appearing in all three matrices in the relatively narrow regions around 1221-1225, 1343-1349, and 1438-1444 cm -1 (Fig.…”

“…2 and 3. A comprehensive listing of the bands observed in our experiments, and their tentative interpretation, as well as the previous assignments by Klaeboe et al [6] are collected in Table 3*. Very often matrix isolation yields excellent quality spectra with sharp absorption bands, which exhibit little perturbation when compared with the gas phase.…”

“…The molecule has a low, C 1 symmetry, and the most likely explanation of the observed multiple strong bands seems to lie in very strong Fermi resonances between the N 3 asymmetric frequency, the CN stretching frequency, and combinations and overtones of the numerous lower frequency vibrational modes expected in this region. It should be mentioned that also a previous study [6] suggested a similar complexity in this region even in the gas phase spectrum. A rather weak band observed in all three matrices around 2255-2259 cm -1 , but absent from the spectra of azidoacetone to be discussed below is undoubtedly due to the CN stretching vibration (Figs.…”

“…The compounds were studied both in solution and in solid phase, and the relative volatility of some of them, for example azidoacetonitrile (N 3 CH 2 CN, in this work abbreviated as AzN) and azidoacetone (N 3 CH 2 COCH 3, AzC), allows their studies in the gas phase [6]. The thermal decomposition of these two compounds was recently studied using ultraviolet photoelectron spectroscopy (UVPES) and matrix-isolation spectroscopy in solid nitrogen, as part of a general project on decomposition of aliphatic azides [7,8].…”

Insights into the Thermal and Photochemical Reaction Mechanisms of Azidoacetonitrile. Spectroscopic and MS‐CASPT2 Calculations

“…The present work is an experimental and theoretical study of both the photochemical as well as the thermal decomposition of azidoacetonitrile (AZN), a well‐known organic aliphatic azide, firstly prepared in 1932 by Freudenberg and later characterized by conventional FTIR spectroscopy in solid matrix as well as thermodynamically . In this work, experimental data dealing with the photochemical decom‐position of AZN are taken from the article of Boyer et al., while the experimental data concerning to the thermal decomposition of the azide were obtained by ourselves.…”