Hydrogen Bonded 3D Supramolecular Architectures of Three Saccharinate Salts

Abstract

Three saccharinate salts (2-aminopyrimidine): (saccharin) (1), (4-phenylthiazol-2-amine): (saccharin) (2), and (2-methylquinoline): (saccharin) (3) were prepared and structurally characterized by X-ray crystallography. Salt 1 crystallizes in the monoclinic, space group P2(1)/c, with a = 7.1782(9) Å, b = 13.5105(16) Å, c = 12.2251(12) Å, β = 93.3410(10)°, V = 1183.6(2) ų, Z = 4. Compound 2 crystallizes in the triclinic, space group P-1, with a = 7.4584(7) Å, b = 8.6930(9) Å, c = 12.9179(14) Å, α = 108.952(2)°, β = 91.7510(10)°, γ = 97.2280(10)°, V = 783.57(14) ų, Z = 2. Compound 3 crystallizes in the monoclinic, space group P2(1)/c, with a = 7.781(8) Å, b = 19.4209(19) Å, c = 10.9719(12) Å, β = 107.7390(10)°, V = 1579.2(16) ų, Z = 4. The different hydrogen bonding interaction modes of the saccharinate anions and the cations lead to 3D network structure, 3D staircase structure, and 3D ABAB layer structure for 1, 2, and 3 respectively. Despite variations in the cation shape on the aromatic N–heterocyclic compounds, there all existed strong intermolecular N–H⋯O(carbonyl) hydrogen bonds. In compounds 1, and 3 the N⁺–H⋯O interaction between the N⁺–H group of the cation and the C=O group of the saccharinate anion is the most important interaction in this family of salts. However, in 2, there was a N–H⋯O interaction between the amino proton and the C=O group of the saccharinate anion. At the next level, the aromatic C–H proton interacts with the sulfonyl O atom. There are also π–π interactions in compounds 1–2, there is CH₃–π interaction in 3. Under these interactions the three compounds exhibit synthons I–III respectively. These interactions are responsible for the high-yielding supramolecular assembly of N-containing aromatic bases and the saccharinate into salts.

Graphical Abstract

Due to the collective weak interactions, the complexes displayed 3D structure.