Intramolecular Hydrogen Bond Interaction in Selected Diols

Abstract

Solute descriptors characterizing major interactions in solution are accessible based on quantitative structure-property relationships (QSPR). Parameters of such relationships should be additive for functional groups. Because added parameters of monools describing molecular interaction do not meet the experimentally found intermolecular interaction parameters of diols and triols, it is assumed that intramolecular hydrogen bonding is responsible for these deviations. In this paper the intramolecular interactions in several diols are illuminated by IR measurements. Particularly, the influence of intramolecular hydrogen bonding on the absorbances of the OH groups is subject of investigation. Two conclusions can be drawn from the results: The terminal OH groups, which underlie an OH–OH interaction, also change their absorbance intensity in comparison to the free OH band. Secondly, the intermolecular interaction potential is strongly affected by intramolecular hydrogen bonding. The first observation is tentatively quantified as well as the position of the equilibrium between intramolecularly bonded and free diols.

Molar heat capacities for (1-butanol+1,4-butanediol, 2,3-butanediol, 1,2-butanediol, and 2-methyl-2,4-pentanediol) as function of temperature

“…It must be pointed out here that 1,4BD is one of the very interesting a,x-alkanediols which are intramolecularly associated [4,5]. In the case of 1,4 positions of the OH groups, a rather strong internal hydrogen bond will be formed because the seven-membered associate ring is energetically favoured [5].…”

“…In the case of 1,4 positions of the OH groups, a rather strong internal hydrogen bond will be formed because the seven-membered associate ring is energetically favoured [5]. Unfortunately, 1,4BD is also used as an illicit drug known by recreational users as ''One Comma Four'' or ''One Four Bee''.…”

1,2-Propanediol. Comprehensive experimental and theoretical study

“…There are 14 stable conformers in the 1,2-propanediol molecule (see table S2 in Supporting Information). Several theoretical and experimental studies on the conformational equilibrium of 1,2-ethanediol and 1,2-propanediol have been reported [35][36][37]. In this work conformational equilibrium and relative energies of 1,2-ethanediol and 1,2-propanediol were calculated by using the G3MP2 method.…”

The effect of temperature and pressure on acoustic and thermodynamic properties of 1,4-butanediol. The comparison with 1,2-, and 1,3-butanediols

“…In our opinion, the present results for 1,4BU are consistent with the previous findings, i.e., the P int (p) dependences for 1,4BU show no maxima in the investigated p and T ranges, and the ability to form intramolecular hydrogen bonds among isomeric butanediols is highest. As IR studies show, the ability to form intramolecular hydrogen bonds increases generally from the five-membered ring of 1,2-diols, via the six-membered ring of 1,3-diols, to the seven-membered ring of 1,4-diols [43][44][45] (in butanediols from 1,2 positions (primary and secondary alcohol group), via 1,3 positions (primary and secondary alcohol group), to 1,4 positions (two secondary alcohol group)). Obviously, at the same time, the presence of the intramolecular hydrogen bonding changes the overall activity of the molecule to form intermolecular bonds.…”