Ten Salts and One Co-crystal Fabricated from 4-methylbenzo[ d ]thiazol-2-amine and Acids through Combination of Classical H-bonds and Weak Noncovalent Interactions

Eleven crystalline compounds of 4-methylbenzo[ d ]thiazol-2-amine with different acids have been prepared and featured by XRD analysis, offering further insight into the foundation of 4methylbenzo[ d ]thiazol-2-amine-acid assemblies. It also shows the importance of the functional groups at the acids in the assembly processes. FT-IR spectroscopy analyses were used as complementary techniques to verify the deprotonation of the carboxylic group, allowing an unambiguous identification of the co-crystals/salts. The result unveils that among the investigated crystalline solids 1 -4 and 6 -11 the aryl N in thiazole cores are protonated and each HL + makes use of thiazole nitrogen atom and amino nitrogen atom to form N -H center dot center dot center dot O H-bonds with the deprotonated acids. 5 is a cocrystal sustained by the neutral N -H center dot center dot center dot O/O -H center dot center dot center dot N H-bonds. Apart from the N -H center dot center dot center dot O H-bonds, the O -H center dot center dot center dot O H-bonds were present at 8 and 10 -11 too. 1-2 had the additional N -H center dot center dot center dot S H-bonds. The O -H center dot center dot center dot N H-bond was made in 5 . Further analysis of the crystal packings told that a different bunch of additional NH center dot center dot center dot C, CH center dot center dot center dot O/CH 2 center dot center dot center dot O/CH 3 center dot center dot center dot O, CH center dot center dot center dot N, CH 3 center dot center dot center dot S, CH center dot center dot center dot Cl/CH 3 center dot center dot center dot Cl, CH center dot center dot center dot pi/CH 3 center dot center dot center dot pi, NH center dot center dot center dot pi, O center dot center dot center dot pi, O center dot center dot center dot S, S center dot center dot center dot C, S center dot center dot center dot pi, Br center dot center dot center dot S, CH 3 center dot center dot center dot S and pi center dot center dot center dot pi contacts contribute to the stabilization and expansion of the total structures. By combination of the various weak nonbonding associations these structures took on homo/hetero supramolecular synthons. The association of the L and acid is based on the typical R 2 2 (8) synthon except 2 . For the synergism of these weak bonds, 1 -11 display 1D-3D structures. (c) 2022 Published by Elsevier B.V.