Advances in the Supramolecular Chemistry of Tetracoordinate Boron-Containing Organic Molecules into Organogels and Mesogens

Abstract

Boron-containing organic compounds are well accepted as a class of compounds having excellent photophysical properties. In addition to the unique photophysical properties, the ease of synthesis and structural robustness make tetracoordinate boron complexes ideal for a variety of applications. While significant light has been thrown on their luminescence properties, there is no collective attention to their supramolecular chemistry. In this mini review, we discuss the progress made in the supramolecular chemistry of these compounds which includes their utility as building blocks for liquid crystalline materials and gels largely driven by various non-covalent interactions like H-bonding, CH-π interactions, BF-π interactions and Van der Waals forces. The organoboron compounds presented here are prepared from easy-to-synthesize chelating units such as imines, diiminates, ketoiminates and diketonates. Moreover, the presence of heteroatoms such as nitrogen, oxygen and sulfur, and the presence of aromatic rings facilitate non-covalent interactions which not only favor their formation but also helps to stabilize the self-assembled structures.

Isomer Selective Thermosalience and Luminescence Switching in Organic Crystals

“…Boron-containing organic compounds are attractive for their promising luminescence and optoelectronic properties. − Table S4 shows the photophysical properties of 1α , 1β , and 2 in their crystal form. The absorption profiles of these compounds were typical of this class of compounds, whereas their emission spectra were dominated by broad peaks (Figure a,b).…”

Controlling the aggregation and assembly of boron‐containing molecular and polymeric materials

“…Numerous other boron chromophore‐based supramolecular polymers have since been developed. [ 56,57 ] Importantly, molecular recognition events can enable control over the triggered assembly‐disassembly of such stacked constructs. In one example, Maeda et al.…”

“…Numerous other boron chromophore-based supramolecular polymers have since been developed. [56,57] Importantly, molecular recognition events can enable control over the triggered assembly-disassembly of such stacked constructs. In one example, Maeda et al attached two arylpyrrole units to boron diketonates (B2) and investigated their assemblydisassembly in response to anion recognition events.…”

A visible-light activated ROS generator multilayer film for antibacterial coatings

“…21,22 Coordination of boron to the electron-rich organic chelates leads to electron delocalization from the organic chelate to the empty p-orbital of boron, thereby inducing planarity and imparting stability to the boron complex. [23][24][25][26][27][28][29] Boron coordination also results in red-shifted absorption and emission as compared to the corresponding chelating units. The properties of boroncontaining organic compounds can be easily tuned by appropriately choosing the starting materials like amines and aldehydes which react readily to form the corresponding chelating units.…”