A polymorph of 2,4-dinitro-phenyl-hydrazine.

ABSTRACT: The crystal structure of a previously unreported polymorph (form II) of 2,4-dinitro-phenyl-hydrazine (DNPH), C6H6N4O4, was determined at 90?K. The first polymorph (form I) is described in the monoclinic space group P21/c [Okabe et al. (1993 ?). Acta Cryst. C49, 1678-1680; Wardell et al. (2006 ?). Acta Cryst. C62, o318-320], whereas form II is in the monoclinic space group Cc. The mol-ecular structures in forms I and II are closely similar, with the nitro groups at the 2- and 4-positions being almost coplanar with the benzene ring [dihedral angles of 3.54?(1) and 3.38?(1)°, respectively in II]. However, their packing arrangements are completely different. Form I exhibits a herringbone packing motif, whereas form II displays a coplanar chain structure. Each chain in form II is connected to adjacent chains by the inter-molecular inter-action between hydrazine NH2 and 2-nitro groups, forming a sheet normal to (101). The sheet is stabilized by N-H?? inter-actions.

SUBMITTER: Amimoto K 

PROVIDER: S-EPMC3588540 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature