Variation in supramolecular arrangements of hydrazones, o-H2NC6H4CMeNNHC6H4X (XH, o-, m- and p-NO2), derived from o-aminoacetophenone and phenylhydrazines
作者:R. Alan Howie、Thomas C. Baddeley、James L. Wardell、Solange M.S.V. Wardell
DOI:10.1016/j.molstruc.2012.04.023
日期:2012.8
The crystal structures of four hydrazones, 1, derived from phenylhydrazines, XC6H4NHNH2 (X=H, o-NO2, m-NO2 or p-NO2) with 2-aminoacetophenone are reported, as is the mono hydrochloride, (2: X=m-NO2), of (1: X=m-NO2). Consistent strong intramolecular hydrogen bonds in 1 are of the type,N-H-(amino)center dot center dot center dot N-(hydrazono), while (1: X=m-NO2) portrays an additional N-H-(hydrazono)center dot center dot center dot O-(nitro), intramolecular hydrogen bond. Of interest, different sets of strong intermolecular interactions are found even among the nitro derivatives, 1. In (1: X=o-NO2), the strongest intermolecular interactions are N-H-(amino)center dot center dot center dot O-(nitro) hydrogen bonds, while in (1: X=m-NO2 and p-NO2), both N-H-(hydrazono)center dot center dot center dot O-(nitro) and N-H-(amino)center dot center dot center dot N-(amino) are present. These strong intermolecular hydrogen bonds coupled with different combinations of some of C-H center dot center dot center dot O, pi-pi stacking interactions and N-O center dot center dot center dot pi generate different supramolecular arrays for (1: X = nitro): 2-D, 2-D and 3-D, respectively for (1: X=o-NO2), for (1: X=m-NO2) and (1: X=p-NO2). In (1: X=H), the major intermolecular interactions are N-H-(hydrazono)center dot center dot center dot N-(amino hydrogen bonds: these, supplemented by weaker N-H center dot center dot center dot pi and C-H center dot center dot center dot pi interactions, generate a two-dimensional array.While significant changes in the intermolecular interactions result on formation of the salt, (2: X= m-NO2) from (1: X=m-NO2), the strong N-H-(amino)center dot center dot center dot N-(hydrazono) intramolecular hydrogen bonds persist. Strong intermolecular hydrogen bonds found in (2: X=m-NO2) are of the types N-H center dot center dot center dot Cl (both hydrazone and amine), N-H-(amino)center dot center dot center dot O-(nitro): these coupled with weaker C-H center dot center dot center dot O, N-O center dot center dot center dot pi, and pi-pi generate a three dimensional array. (C) 2012 Elsevier B.V. All rights reserved.