Alcohols infrared spectra, 519 table

This moderately air-sensitive niobium salt is soluble in a wide variety of solvents, such as aromatic hydrocarbons, ethers, ketones, alcohols, and water, to give very air-sensitive solutions. The solid is also somewhat light-sensitive and should be stored in the dark. It is indefinitely stable at room temperature under nitrogen. The infrared spectrum of the compound in the carbonyl region is given in Table I. 

The infrared spectrum of sotalol hydrochloride is depicted in Figure 4. The spectrum was obtained on a KBr disk using a Nicolet 20 SX Fourier Transform infrared spectrometer. Diagnostic peaks were observed at 3570 cm (secondary alcohol, free) 3410 cm l (secondary alcohol, H-bonded) 2700-2800 cm l and 2950-3200 cm l (hydrochloride) 1325 cm (S=0 asymmetric stretch) 1154 cm l (S=0 symmetric stretch). The peaks are presented in Table I. 

A linear correlation between the heats of formation of hydrogen-bonded associates and the shifts in the O—H vibrations due to the above effect was first pointed out by Badger and Bauer [Ba 37]. More recently, Drago et al [Dr 63, Dr 69, Dr 70, Ep 67, Jo 66, No 70, Pu 67, Pu 69, Sh 70, Wa 64] made comparisons between the heats of reaction of various phenols and alcohols with different donor molecules and the resulting O—H vibration shifts. From their numerous experimental data they constructed empirical equations by means of which the heat of formation of an associate can be calculated from the O—H vibration shift, which is simply read off the infrared spectrum. Some of these empirical equations are presented in Table 5.1. 

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