Abstract
A new monoclinic polymorph of the title compound, C(8)H(12)N(4), in the space group P2(1)/n (Z = 4) is reported. The previously known form was also monoclinic, P2(1)/c (Z = 4), but the unit-cell parameters and crystal packing were different [Shoja & Saba (1993 ▶). Acta Cryst. C49, 354-355]. The hexa-hydro-pyrimidine ring of the title compound adopts a chair conformation with a diequatorial substitution and with the CH(2)-C N groups oriented nearly parallel and in the same direction [NC-CH(2)⋯CH(2)-CN pseudo torsion angle = -6.27 (18)°]. In the crystal, inter-molecular C-H⋯ N hydrogen bonds connects the mol-ecules into a chain along the b axis.