2,3-Dichloro-D-β-homophenylglycine

The asymmetric unit of the title compound, C(9)H(4)S(7), contains two independent mol-ecules, in one of which the central five-membered ring is disordered over two orientations in a 0.924 (3):0.076 (3) ratio. The mol-ecular skeleton is almost planar: the average distance of the atoms from their mean plane is 0.128 (7) Å in the ordered mol-ecule, and 0.088 (5) and 0.123 (2) Å in the major and minor disorder components, respectively. The ordered and disordered mol-ecules form separate columns by stacking along the b axis. Adjacent columns inter-act via short S⋯S [3.33 (2), 3.434 (3), 3.444 (2), 3.503 (2), 3.519 (3) and 3.53 (4) Å] and S⋯H [2.814 (2), 2.87 (7), 2.92 (2), 2.9269 (18), 2.93 (2), 2.94 (2), 2.939 (2), 2.967 (2) and 2.974 (1) Å] contacts.

In the title compound, C19H17Cl2N3O2, there are three mol-ecules (A, B and C) in the asymmetric unit and each differs in the conformation adopted. As a result of steric repulsion, the amide group is rotated with respect to both the dichloro-phenyl and 2,3-dihydro-1H-pyrazol-4-yl rings, making dihedral angles of 44.5 (2) and 56.2 (2)°, respectively in A, 51.1 (2) and 54.1 (2)° in B, and 53.8 (2) and 54.6 (2)° in C. The dihedral angles between the dichloro-phenyl and 2,3-dihydro-1H-pyrazol-4-yl rings are 54.8 (2), 76.2 (2) and 77.5 (2)° in mol-ecules A, B and C, respectively, while the 2,3-dihydro-1H-pyrazol-4-yl and phenyl rings make dihedral angles of 45.3 (2), 51.2 (2) and 42.8 (2)°, respectively. In the crystal, two of the mol-ecules are linked through N-H⋯O hydrogen bonding to an adjoining mol-ecule, forming dimers of the R2(2)(10) type, while the third mol-ecule forms such dimers with itself. C-H⋯O inter-actions link the dimers.