Stacking among the clips of the poly-aromatic rings of phenazine with hydroxy-aromatics and photophysical properties

Abstract

Clip-like arrangements of molecules in the cocrystals of phenazine with hydroxy-aromatics in their respective self-assemblies and photophysical properties were presented. Phenazine cocrystals with 1,2dihydroxybenzene provided assembly with butterfly-like arrangements. In these cocrystals, the phenazine molecules occurred in parallel pairs having extensive p-stacking. The clip-like cocrystals with 1,3-dihydroxybenzene also exhibited parallel pairs of phenazine molecules that were parallel cofacial pstacked. The hydrated cocrystals of phenazine with 1,2,3-trihydroxybenzene had chains of parallel cofacial phenazine rings having three distinguishable p-separation distances among the centroids of the phenazine rings. Also, 2,7-dihydroxynaphthalene formed a clip-like cocrystal with phenazine, which encapsulated an additional molecule of phenazine. This cocrystal also provided chain-like parallel arrangements of the phenazine molecules. The emission and quantum yields of the cocrystals were determined by the integrating sphere method, which indicated that only the cocrystal of phenazine with 2,7-dihydroxynaphthalene showed monomer-like emission of phenazine and the rest of the cocrystals were in a quenched state. In the solution phase, quenching of the emission of hydroxynaphthalene was observed when phenazine was added to an independent solution of 2,7-dihydroxynaphthalene or another hydroxynaphthalene. However, when hydroxybenzenes were added to a solution of phenazine, fluorescence enhancements of phenazine occurred due to photo-electron transfer. Fig. 1 (a) Some possible hydrogen-bonded assemblies of phenazine with aromatic diols and (b) structures of phenazine and different organic aromatic diols used in this study.33404 | RSC Adv., 2019,9,[33403][33404][33405][33406][33407][33408][33409][33410][33411][33412] This journal is

Effects of Gamma Radiation on Single- and Multicomponent Organic Crystalline Materials

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Ternary and quaternary cocrystals of 2,7-dihydroxynaphthalene: systematic design with a large synthon module

“…Some of the reported binary cocrystal structures of DHN also indicated the same. 20,21 The coformers chosen for this study include phenazine (PHN), acridine (ACR), 2,3,5,6-tetramethylpyrazine (TMP), 1,10-phenanthroline (PHENAN), and quinoxaline (QUIN). Apart from the pyridine-based coformers, pyrene (PYR) and phenanthrene (PHEN) were also used as coformers in a few cases (Fig.…”

Synthetic Strategies toward Higher Cocrystals of Some Resorcinols

“…In this context, we mention the recent study of Mukherjee and Ahsan, who have reported the crystal structures of six ternaries, two ternary solvates, and two quaternary cocrystals of DINAP. 53 We obtained 12 structures (6 binaries, 3 binary solvates, and 3 ternaries); a binary cocrystal reported by Brahma et al 61 is also taken into consideration, and the following discussion pertains to all these 23 structures (6 + 2 + 2 + 12 + 1). Among the seven binaries, we observed the closed synthon in DINAP:TMP, the intercalated "Type A" synthon in DINAP:-PHEN, and the continuous "Type B" synthon in DI-NAM:DMQXN.…”