Crystal Structure, Thermal Behavior, and Photochemical Reactivity of a Series of Co-Crystals of trans-1,2-Bis(4-pyridyl) Ethylene with Dicarboxylic Acids

Abstract

A series of co-crystals of trans-1,2-bis(4-pyridyl) ethylene (bpe) with aliphatic saturated or unsaturated dicarboxylic acids, of the type [(bpe)(L)] (L = dicarboxylic acid), were prepared and characterized by single crystal X-ray crystallography. In all cases chains of the type acid•••bpe•••acid were formed via strong O−H•••N hydrogen bonds. The chains were further linked between them by weak C−H•••O hydrogen bonds, π−π and herringbone interactions to form three-dimensional structures. Thermal analysis showed considerable elevation of the melting/decomposition point of the co-crystals with respect either to both components or to bpe, ascribed to the formation of multiple complementary C−H•••O bonds as well as to π−π interactions between the two conformer molecules. When L = fumaric acid, the two components stack separately with their CC bonds strictly parallel between them at 3.83 Å from one another. However, photodimerization reaction takes place only between the olefin bonds of bpe. Photodimerization reaction between one CC bond of the acid and that of bpe was also induced when L = trans,trans-muconic acid.

Two Cd(II) complexes derived from mercapto-triazole ligands: syntheses, crystal structures, and luminescent properties

“…In the equatorial plane, the Cd-N bond length (2.477(2) Â) is somewhat greater than those 2(b)). The N---0 and C---0 distances are comparable to those observed in other complexes [35,36]. In addition, free methanols are found in the lattice of 2 with intermolecular hydrogen bonding interactions between free methanol molecules, coordinated water and sulfate with the C---0 (methanol/water) distance of 3.414(12)Â and the O---O (methanol/sulfate) distance of 2.758(9) Â (figure 2(c)), respectively.…”

The crystal engineering of radiation-sensitive diacetylene cocrystals and salts

“…S11 †), compared to 150 C for 4. 61 The similar melting temperatures for the two cocrystals are expected due to the isostructural nature of these materials. The FTIR spectra for these cocrystals display a hydrogen-bonded carbonyl stretch at 1683 cm À1 and 1688 cm À1 respectively, compared to 1692 cm À1 in pure 1, implying slightly stronger hydrogen bonding ( Fig.…”

Design of Green‐Emitting Salts from Substituted Pyridines: Understanding the Solid‐State Photodimerization of trans‐1,2‐bis(4‐pyridyl)ethylene

“…Various crystal engineering principles have effectively been utilized to orient the C=C bonds of bpe in the solid state to make them ready for photodimerization [13,14] . To promote the photodimerization of olefinic C=C bonds in bpe , organic co‐crystals, [15,16] organic salts, [17–19] discrete coordination complexes [20] and coordination polymers [21,22] have been used with a focus on solid‐state [2+2] photodimerization. Among the protonated salts; CF 3 COOH, [19] and CF 3 SO 3 H [18] have been used to induce stacking of the C=C bonds within bpe crystals to set the scene for [2+2] photodimerization.…”