In:
Acta Crystallographica Section C Crystal Structure Communications, International Union of Crystallography (IUCr), Vol. 68, No. 7 ( 2012-07-15), p. o270-o278
Abstract:
To examine the roles of competing intermolecular interactions in differentiating the molecular packing arrangements of some isomeric phenylhydrazones from each other, the crystal structures of five nitrile–halogen substituted phenylhydrazones and two nitro–halogen substituted phenylhydrazones have been determined and are described here: ( E )-4-cyanobenzaldehyde 4-chlorophenylhydrazone, C 14 H 10 ClN 3 , (I a ); ( E )-4-cyanobenzaldehyde 4-bromophenylhydrazone, C 14 H 10 BrN 3 , (I b ); ( E )-4-cyanobenzaldehyde 4-iodophenylhydrazone, C 14 H 10 IN 3 , (I c ); ( E )-4-bromobenzaldehyde 4-cyanophenylhydrazone, C 14 H 10 BrN 3 , (II b ); ( E )-4-iodobenzaldehyde 4-cyanophenylhydrazone, C 14 H 10 IN 3 , (II c ); ( E )-4-chlorobenzaldehyde 4-nitrophenylhydrazone, C 13 H 10 ClN 3 O 2 , (III); and ( E )-4-nitrobenzaldehyde 4-chlorophenylhydrazone, C 13 H 10 ClN 3 O 2 , (IV). Both (I a ) and (I b ) are disordered (less than 7% of the molecules have the minor orientation in each structure). Pairs (I a )/(I b ) and (II b )/(II c ), related by a halogen exchange, are isomorphous, but none of the `bridge-flipped' isomeric pairs, viz. (I b )/(II b ), (I c )/(II c ) or (III)/(IV), is isomorphous. In the nitrile–halogen structures (I a )–(I c ) and (II b )–(II c ), only the bridge N—H group and not the bridge C—H group acts as a hydrogen-bond donor to the nitrile group, but in the nitro–halogen structures (III) (with Z ′ = 2) and (IV), both the bridge N—H group and the bridge C—H group interact with the nitro group as hydrogen-bond donors, albeit via different motifs. The occurrence here of the bridge C—H contact with a hydrogen-bond acceptor suggests the possibility that other pairs of `bridge-flipped' isomeric phenylhydrazones may prove to be isomorphous, regardless of the change from isomer to isomer in the position of the N—H group within the bridge.
Type of Medium:
Online Resource
ISSN:
0108-2701
DOI:
10.1107/S0108270112026443
DOI:
10.1107/S0108270112026443/fg3255sup1.cif
DOI:
10.1107/S0108270112026443/fg3255Iasup2.hkl
DOI:
10.1107/S0108270112026443/fg3255Ibsup3.hkl
DOI:
10.1107/S0108270112026443/fg3255Icsup4.hkl
DOI:
10.1107/S0108270112026443/fg3255IIbsup5.hkl
DOI:
10.1107/S0108270112026443/fg3255IIcsup6.hkl
DOI:
10.1107/S0108270112026443/fg3255IIIsup7.hkl
DOI:
10.1107/S0108270112026443/fg3255IVsup8.hkl
DOI:
10.1107/S0108270112026443/fg3255Iasup9.cml
DOI:
10.1107/S0108270112026443/fg3255Ibsup10.cml
DOI:
10.1107/S0108270112026443/fg3255Icsup11.cml
DOI:
10.1107/S0108270112026443/fg3255IIbsup12.cml
DOI:
10.1107/S0108270112026443/fg3255IIcsup13.cml
DOI:
10.1107/S0108270112026443/fg3255IIIsup14.cml
DOI:
10.1107/S0108270112026443/fg3255IVsup15.cml
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
2012
detail.hit.zdb_id:
2025703-X
SSG:
13
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