title: A chain of edge-fused rings generated by the combination of an N-H...O hydrogen bond and an iodo-nitro interaction in 2-iodobenzaldehyde 4-nitrophenylhydrazone versus disordered and effectively isolated molecules in 2-iodobenzaldehyde 2,4-dinitrophenylhydrazone.
abstract: Molecules of 2-iodobenzaldehyde 4-nitrophenylhydrazone, C(13)H(10)IN(3)O(2), are effectively planar and are linked by an N-H...O hydrogen bond [H...O = 2.04 A, N.O = 2.905 (6) A and N-H...O = 166 degrees ] and a two-centre iodo-nitro interaction [I...O = 3.361 (4) A] into a chain of edge-fused R(3)(3)(18) rings. There are no direction-specific interactions between adjacent chains. Molecules of 2-iodobenzaldehyde 2,4-dinitrophenylhydrazone, C(13)H(9)IN(4)O(4), are disordered over two orientations with occupancies of 0.681 (5) and 0.319 (5). In the major orientation, there are no direction-specific intermolecular interactions, while for the minor form, a single C-H...O hydrogen bond generates centrosymmetric dimers.
authors.affiliation: School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, Scotland. cg@st-andrews.ac.uk
authors.forename: Christopher
authors.initials: C
authors.lastname: Glidewell
authors.forename: John N
authors.initials: JN
authors.lastname: Low
authors.forename: Janet M S
authors.initials: JM
authors.lastname: Skakle
authors.forename: James L
authors.initials: JL
authors.lastname: Wardell