Halobenzyl alcohols as structurally simple organogelators

Abstract

We report 11 simple halobenzyl alcohols, each comprising of only 16 atoms, as organogelators for aliphatic hydrocarbon solvents. Their self-assembly is similar in both gel and crystal states and involve OH⋯O, CH⋯O, CH⋯π, O⋯X, CH⋯X and X⋯X interactions.

A Review on Low‐Molecular‐Weight Gels Driven by Halogen‐Effect

“…In some cases, gelator has a similar mode of packing in crystal and gel state by comparing the powder X ray diffraction (PXRD) patterns of crystals and xerogels. If these patterns match well, the crystal structure can be used to understand the molecular assembly in the gel [32,44,56–58] . Such strategy cannot be used in the absence of single crystals of the gelator.…”

“…In single‐component systems, the introduction of halogen has a significant effect on the self‐assembly of low‐molecular‐weight gelators in organic solvents or in polar water, proving to be a promising strategy for effective regulation of gels properties. The reason could be explained by two main aspects [31–33] . The electron absorption properties and heavy atom effect of halogen substituents are beneficial to enhance the intermolecular interaction of halogenated compounds.…”

“…Sureshan and the co‐worker reported a series of structurally very simple benzyl alcohols‐based gelators consisting of only sixteen atoms, all of which were able to form gels in a variety of aliphatic hydrocarbon solvents (Scheme 5). [32] Due to the similar XRD patterns of gels and crystals, it was feasible to elucidate the molecular‐level interactions involved in the self‐assembly in the gel state by single crystal X‐ray structures. Gel fiber formation of each compound involved multiple types of hydrogen bonds (OH…O, CH…O & CH…π) and non‐covalent interactions of halogen atoms (halogen…halogen, halogen bonding and CH…halogen).…”

“…In the past two decades, halogen bonding as a new method to achieve LWMGs has attracted wide attention. Halogenation is a minimal structural modification and may give rise to the rich variety of non‐covalent interactions from halogen atoms [31–33] . In fact, halogenation has been shown to be an effective strategy for influencing supramolecular organization, enabling different kinds of small molecules to form gels in organic solvents, water, and liquid crystals.…”

Is the Fourier Transform Infrared Free-OH Band of t-Butanol Only from Free OHs? Case Studies on the Binary Systems of the Alcohol with CCl4 and CHCl3

“…Structures and properties of liquids containing alcohols and their H-bonding interactions have been of interest in many laboratories. − Among various alcohols, tert -butyl alcohol ( t -BuOH) has received much attention. − Relative to some other aliphatic alcohols such as methanol and ethanol, t -BuOH forms smaller H-bonded aggregates due to its special geometric shape and stronger hydrophobic character . Yonker et al found that the H-bonding aggregates in tertiary alcohols in general, and particularly in t -BuOH, are mainly cyclic.…”