Influence of different aryl substitution on the crystal structures of benzil monohydrazone and dibenzil azine parent compounds

Abstract

A series of benzil monohydrazones (1a, 1d) and corresponding dibenzil azines (2a-2d) featuring different p-aryl substituents have been synthesized and studied in regard of their crystal structures. Configurational and conformational properties as well as non-covalent interaction and packing behaviour of the molecules connected with the different substitution are discussed. The dibenzil azine 2a was found as a polymorph with reference to a known crystal structure.

Crystal structure of (Z)-2-[(E)-2-benzylidenehydrazin-1-ylidene]-1,2-diphenylethanone

“…The molecule adopts a Z conformation with respect to the C2 N1 bond and an E conformation with respect to the C3 N2 bond, with the carbonyl atom O1 and the C11-C16 phenyl ring located on opposite sides of the dibenzylidenehydrazine plane. The bond lengths and angles in the title molecule agree reasonably well with those found in closely related structures (Abbasi et al, 2007;Wieland et al, 2011).…”

“…The closest to the title structure are 2- et al, 2007), with an hydroxy substituent in the p position on the equivalent of the benzene ring, and 1,2-diphenyl-2-[4-(4pyridyl)benzylidenehydrazono]ethan-1-one, with a pyridyl ring in the same position . Two reports of polymorphs of the symmetrical 2,2 0 -(1,2-hydrazinediylidene)bis(diphenylethanone) have also appeared Wieland et al, 2011)…”

Theoretical insight into the disordered structure of (Z)-2-[(E)-(4-methoxybenzylidene)hydrazinylidene]-1,2-diphenylethanone: the role of noncovalent interactions

“…52 (5.39), N 12.56 (12.49). The single-crystal structure of BMH was also determined and is essentially the same as that reported by Wieland et al (2011) (see supporting information).…”

“…418.4-419.0 K, reference m.p. 148-150 (Hauptmann & Wilde, 1969), 147-150 (Carter & Hulse, 1982), 151 (Wieland et al, 2011) and 427-429 K (Alonazy et al, 2009)]. Elemental analysis found (calculated) for C 14 H 12 N 2 O (%): C 75.04 (74.98), H 5.…”

Coumarin-based benzilmonohydrazone as a new proton-sensitive fluorescencedye: synthesis and investigation of photophysical and acidochromic properties

“…Compound 3 was synthesized by simple condensation between benzil (C) and hydrazine hydrate in ethanol utilizing a reported method [21]. Yield: 95%; mp:…”