2-Amino-4,6-dimethyl-pyrimidine-benzoic acid (1/1).

The crystal of the title compound, C(6)H(9)N(3)·C(7)H(6)O(2), contains tetra-meric hydrogen-bonded units comprising a central pair of 2-amino-pyrimidine mol-ecules linked across a centre of inversion by N-H⋯N hydrogen bonds and two pendant benzoic acid mol-ecules attached through N-H⋯O and O-H⋯N hydrogen bonds. These hydrogen-bonded units are arranged into layers in (002).

4-Methyl-6-phenyl-pyrimidin-2-amine.

The title compound, C(11)H(11)N(3), was synthesized as part of our research into functionalized pyrimidines. It crystallizes with two independent mol-ecules in the asymmetric unit that differ only in the twist between the two aromatic rings; the torsion angles between the rings are 29.9 (2) and 45.1 (2)°. The crystal packing is dominated by inter-molecular N-H⋯N hydrogen bonds between independent and equivalent mol-ecules, forming an infinite three-dimensional network.