Crystal structure, hydrogen bonding and Hirshfeld surface analysis of 2-amino-4-meth-oxy-6-methyl-pyrimidinium 4-chloro-benzoate.

In the crystal structure of the title salt, C(6)H(10)N(3)O(+)·C(7)H(4)ClO(2)(-), the dihedral angle between the pyrimidine ring of the 2-amino-4-meth-oxy-6-methyl-pyrimidine cation and the the benzene ring of the 2-chloro-benzoate anion is 2.2†(1)°. In the anion, the benzene ring forms a dihedral angle of 8.5†(2)° with the carboxyl group. The pyrimidine N atom of the cation is protonated and the meth-oxy substituent is essentially coplanar with the parent ring. The protonated N atom and the N atom of the 2-amino group are hydrogen bonded to the 4-chloro-benzoate anion through a pair of N-H⋯O(carbox-yl) hydrogen bonds, forming an R(2)(2)(8) ring motif linked through a centrosymmetric R(2)(4)(8) ring motif, resulting in a pseudo-tetra-meric DDAA array. These units are linked through inter-molecular meth-oxy C-H⋯Cl hydrogen bonds into ribbon-like chains extending along the c-axis direction. The crystal structure also features π-π stacking inter-actions between the rings in the cation and anion [minimum ring centroid separation = 3.7707†(12)†à ].