Issue 39, 2021

5-[(Pyren-9-ylmethyl)amino]isophthalic acid with nitrogen containing heterocycles: stacking, N–H⋯π interactions and photoluminescence

Abstract

Different synthons, π-stackings and intermolecular N–H⋯π interactions guided by partner molecules in the cocrystals of a pyrene-derived dicarboxylic acid were demonstrated. For such a purpose the self-assemblies of a 1 : 1 solvate of dimethylformamide and 1 : 1 cocrystals with 6-phenyl-1,3,5-triazine-2,4-diamine (PTDA), 4,6-dimethylpyrimidin-2-amine (DMPA) or caffeine as well as a 2 : 1 cocrystal with phenazine (Phen) of 5-[(pyren-9-ylmethyl)amino]isophthalic acid (H2L) were studied. The π-stackings among the pyrene rings in these self-assemblies were compared. Different synthons and stacking patterns in these assemblies were also evaluated. The DMF solvate as well as the PTDA cocrystal of H2L had parallel π-stacks of pyrene rings, each of which were organised in a head-to-tail manner (where the head was the substituted end of pyrene and the tail was the opposite end of this). Both the assemblies had intermolecular N–H⋯π interactions. Phenazine was eclipsed between two isophthalic acid units in the phenazine cocrystal. It had η3-N–H⋯π intramolecular interactions. The assembly of the cocrystal with DMPA had pairs of stacked pyrene units organised in a parallel manner. These units were held together by intermolecular η2-N–H⋯π interactions. The cocrystal of caffeine with H2L was obtained as a trihydrate. In this cocrystal the caffeine molecule was sandwiched between the π-stack of the two pyrene rings located on the top and the bottom side of the caffeine molecule. Self-assembly of a 1 : 1 salt, namely a mono-protonated 4,4′-bipyridinium cation with [HL], was also analysed. The 4,4′-bipyridinium salt of the HL anion had the pyrene rings assembled as pairs and were arranged in a head-to-tail arrangement. It lacked intermolecular N–H⋯π interactions. It had unusual pyridine–pyridine R22(6) synthons formed by C–H⋯N hydrogen bonds. Among the cocrystals the caffeine cocrystal was weakly fluorescent with a photoluminescence quantum yield (PLQY) 0.036, whereas the solid sample of the solvate and the other cocrystals as well as the salt of H2L showed negligible emission.

Graphical abstract: 5-[(Pyren-9-ylmethyl)amino]isophthalic acid with nitrogen containing heterocycles: stacking, N–H⋯π interactions and photoluminescence

Supplementary files

Article information

Article type
Paper
Submitted
16 8 2021
Accepted
01 9 2021
First published
01 9 2021

CrystEngComm, 2021,23, 6952-6966

5-[(Pyren-9-ylmethyl)amino]isophthalic acid with nitrogen containing heterocycles: stacking, N–H⋯π interactions and photoluminescence

J. Sendh, M. P. Singh and J. B. Baruah, CrystEngComm, 2021, 23, 6952 DOI: 10.1039/D1CE01099A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements