Crystal structure, hydrogen bonding and Hirshfeld surface analysis of 2-amino-4-methoxy-6-methylpyrimidinium 4-chlorobenzoate

Abstract

In the crystal structure of the title salt, C6H10N3O+·C7H4ClO2−, the dihedral angle between the pyrimidine ring of the 2-amino-4-methoxy-6-methylpyrimidine cation and the the benzene ring of the 2-chlorobenzoate 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 methoxy 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-chlorobenzoate anion through a pair of N—H...Ocarboxyl hydrogen bonds, forming an R22(8) ring motif linked through a centrosymmetric R24(8) ring motif, resulting in a pseudotetrameric DDAA array. These units are linked through intermolecular methoxy C—H...Cl hydrogen bonds into ribbon-like chains extending along the c-axis direction. The crystal structure also features π–π stacking interactions between the rings in the cation and anion [minimum ring centroid separation = 3.7707 (12) Å].

Keywords

• crystal structure
• pseudotetrameric
• pyrimidine