Trithiocyanuric acid: novel cocrystals and analysis of its tautomeric forms

Abstract

Cocrystals of trithiocyanuric acid with 2,2′-bipyridyl [1,3,5-triazinane-2,4,6-trithione–2,2′-bipyridine (2/1), 2C3H3N3S3·C10H8N2, (I)] and 4-methylbenzohydrazide [1,3,5-triazinane-2,4,6-trithione–4-methylbenzohydrazide (1/1), C8H10N2O·C3H3N3S3, (II)] crystallize in the monoclinic crystal system. In the crystals, molecules of both components are linked by hydrogen bonds. The trithiocyanuric acid molecules are connected by N—H...S hydrogen bonds forming R 2 2(8) synthons, which are further organized into chain motifs. Computations based on quantum chemistry methods have been performed for a more detailed description of the observed tautomerism of trithiocyanuric acid.

Co-crystal synthesis of 2- and 4-mercaptopyridines with thiourea and its analogue, trithiocyanuric acid

“…This issue was recently addressed by a combination of structural analysis of experimental data collected in the CSD 18 and computational studies for representative molecular models. 14,15 Due to the fact that all the components of co-crystals I-IV possess proton-donating amino groups and potential protonaccepting centers, e.g., N and S atoms, it is reasonable to assume that the key effect stabilizing the crystal state would be hydrogen bond formation. In fact, this was found to be the case, and the hydrogen bonding network is relatively expanded.…”

“…This issue was recently addressed by a combination of structural analysis of experimental data collected in the CSD 18 and computational studies for representative molecular models. 14,15…”

“…10,11 More information about the application, co-crystal synthesis and interactions of these three chemical species, as well as various theoretical studies, can be found in our earlier works. [12][13][14][15][16][17] These previous papers also include a search for thiourea and trithiocyanuric acid crystals in the Crystal Structure Database (CSD). 18 The search revealed only a few depositions of para-and ortho-mercaptopyridines, two of which were crystals of pure 4-mercaptopyridine (refcode: AKOVOL; 19 AKOVOL01; 20 AKOVOL02; 21 AKOVOL03; 21 AKOVOL04 (ref.…”

“…This paper reports the continuation of our studies on cocrystal synthesis with the use of thiourea and its analogue, trithiocyanuric acid, as components. 12,[14][15][16] It employs a cross-crystallization approach (see graphical abstract) to obtain samples of four new co-crystals (I-IV) of sufficient quality to allow X-ray single-crystal analysis (Scheme 1).…”

“…10,11 More information about the application, co-crystal synthesis and interactions of these three chemical species, as well as various theoretical studies, can be found in our earlier works. 12–17…”