title: 6-Chloro-N(4),N(4)-dimethyl-pyrimidine-2,4-diamine.
abstract: The asymmetric unit of the title compound, C(6)H(9)ClN(4), contains four independent mol-ecules (A, B, C and D). Their main difference is the torsion angles, ranging from 1.6 (5) to 5.9 (5)°, between the methyl group and the pyrimidine plane. A pair of inter-molecular N-H⋯N hydrogen bonds link mol-ecules A and C into a twisted dimer with a dihedral angle of 32.9 (1)° between the two pyrimidine rings, creating an R(2) (2)(8) motif. In the packing, each two mol-ecules of B, C and D form centrosymmetric dimers through two inter-molecular N-H⋯N hydrogen bonds, locally creating R(2) (2)(8) motifs. The dimers of C and D are alternately bridged by A into an infinite zigzag strip, locally creating two different R(2) (2)(8) motifs with dihedral angles of 32.9 (1) and 63.4 (1)° between the pyrimidine rings. Finally, these strips together with the dimers of B associate into a complicated three-dimensional framework.
authors.affiliation: Department of Chemistry, Shandong Normal University, Jinan 250014,  People's Republic of China.
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Pang
authors.forename: Kai
authors.initials: K
authors.lastname: Yu
authors.forename: Bin
authors.initials: B
authors.lastname: Sun
authors.forename: Dian-Shun
authors.initials: DS
authors.lastname: Guo