Supramolecular networks in molecular complexes of pyridine boronic acids and polycarboxylic acids: synthesis, structural characterization and fluorescence properties

Abstract

3- and 4-pyridineboronic acids have been combined with trimesic and pyromellitic acids to give three molecular complexes.

Exploration of the Luminescence Properties of Organic Phosphate Salts of 3‐Quinoline‐ and 5‐Isoquinolineboronic Acid

“…The O ··· O distances in the range of 2.690(2) to 2.777(2) Å are typical for strong O‐H ··· O hydrogen bonding interactions (Figure a and Figure a) , . To the best of our knowledge, so far there are no reports on multicomponent molecular crystals with this synthon.…”

“…Bian et al examined the ultralong phosphorescence behavior of multicomponent materials formed through the self‐assembly of melamine and aromatic acids based on charge‐assisted hydrogen bonding interactions . Our research group reported on the analysis of the supramolecular patterns and evaluation of the luminescence properties of three organic salts derived from 4‐pyridineboronic acid and a series of polycarboxylic acids …”

“…In addition, they serve as useful tools for the design of new functional materials, since they have the ability to form homodimeric and heterodimeric synthons through hydrogen bonds. [15a], The hydroxyl donor groups of the boronic acid ‐B(OH) 2 function can adopt three different conformations, viz. syn , syn, syn,anti and anti,anti , which is relevant for the construction of extensive crystalline networks .…”

“…syn , syn, syn,anti and anti,anti , which is relevant for the construction of extensive crystalline networks . With strong acceptor groups, boronic acids can form strong double‐bridged hydrogen bonding synthons such as the ‐B(OH) 2 ··· – OOC motif formed with carboxylate groups . Although this capability has received attention for applications in molecular recognition, [25] structurally related heterodimeric synthons with other anions such as halides, sulfates/sulfonates and phosphate/phosphonates are practically unexplored.…”

“…Previous reports have shown that nitrogen‐containing boronic acids such as pyridine boronic acids are useful starting reagents for the generation of multi‐component solids in combination with carboxylic acids and metal halides . This, because the nitrogen atoms serve as proton acceptors, enabling the formation of salts with strong charge‐assisted N + –H ··· – X and ‐B(OH) 2 ··· – X hydrogen bonds (X – = carboxylate or metal halide anion).…”