Crystal structures of the co-crystalline adduct 5-(4-bromo-phen-yl)-1,3,4-thia-diazol-2-amine-4-nitro-benzoic acid (1/1) and the salt 2-amino-5-(4-bromo-phen-yl)-1,3,4-thia-diazol-3-ium 2-carb-oxy-4,6-di-nitro-phenolate.

ABSTRACT: The structures of the 1:1 co-crystalline adduct C8H6BrN3S·C7H5NO4, (I), and the salt C8H7BrN3S(+)·C7H3N2O7 (-), (II), obtained from the inter-action of 5-(4-bromo-phen-yl)-1,3,4-thia-diazol-2-amine with 4-nitro-benzoic acid and 3,5-di-nitro-salicylic acid, respectively, have been determined. The primary inter-species association in both (I) and (II) is through duplex R (2) 2(8) (N-H?O/O-H?O) or (N-H?O/N-H?O) hydrogen bonds, respectively, giving heterodimers. In (II), these are close to planar [the dihedral angles between the thia-diazole ring and the two phenyl rings are 2.1?(3) (intra) and 9.8?(2)° (inter)], while in (I) these angles are 22.11?(15) and 26.08?(18)°, respectively. In the crystal of (I), the heterodimers are extended into a chain along b through an amine N-H?Nthia-diazole hydrogen bond but in (II), a centrosymmetric cyclic hetero-tetra-mer structure is generated through N-H?O hydrogen bonds to phenol and nitro O-atom acceptors and features, together with the primary R (2) 2(8) inter-action, conjoined R (4) 6(12), R (2) 1(6) and S(6) ring motifs. Also present in (I) are ?-? inter-actions between thia-diazole rings [minimum ring-centroid separation = 3.4624?(16)?Å], as well as short Br?Onitro inter-actions in both (I) and (II) [3.296?(3) and 3.104?(3)?Å, respectively].

SUBMITTER: Smith G 

PROVIDER: S-EPMC4257302 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature