Crystal structures of 5-amino-N-phenyl-3H-1,2,4-di-thia-zol-3-iminium chloride and 5-amino-N-(4-chloro-phen-yl)-3H-1,2,4-di-thia-zol-3-iminium chloride monohydrate.

ABSTRACT: The crystal and mol-ecular structures of the title salt, C8H8N3S2 (+)·Cl(-), (I), and salt hydrate, C8H7ClN3S2 (+)·Cl(-)·H2O, (II), are described. The heterocyclic ring in (I) is statistically planar and forms a dihedral angle of 9.05?(12)° with the pendant phenyl ring. The comparable angle in (II) is 15.60?(12)°, indicating a greater twist in this cation. An evaluation of the bond lengths in the H2N-C-N-C-N sequence of each cation indicates significant delocalization of ?-electron density over these atoms. The common feature of the crystal packing in (I) and (II) is the formation of charge-assisted amino-N-H?Cl(-) hydrogen bonds, leading to helical chains in (I) and zigzag chains in (II). In (I), these are linked by chains mediated by charge-assisted iminium-N(+)-H?Cl(-) hydrogen bonds into a three-dimensional architecture. In (II), the chains are linked into a layer by charge-assisted water-O-H?Cl(-) and water-O-H?O(water) hydrogen bonds with charge-assisted iminium-N(+)-H?O(water) hydrogen bonds providing the connections between the layers to generate the three-dimensional packing. In (II), the chloride anion and water mol-ecules are resolved into two proximate sites with the major component being present with a site occupancy factor of 0.9327?(18).

SUBMITTER: Yeo CI 

PROVIDER: S-EPMC4647351 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature