2013. 54, 4 UDC 548.73:548.737 STRUCTURES OF TWO HYDRAZONE COMPOUNDS DERIVED FROM 4-METHYLBENZOHYDRAZIDE Y. Lei1, 2, G. Chen1, 3, Q. Yang1, C. Fu2, J. Pan2, T. Li2 1School of City Construction and Environmental Engineering, Chongqing University, Chongqing, P. R. China E-mail: leiyan222@yahoo.cn 3Chongqing Environmental Protection Bureau, Chongqing, P. R. China Received March, 18, 2012 – . 783 – 787 2School of Chemistry and Environmental Engineering, Chongqing Three Gorges University, Chongqing, P. R. China Two hydrazone compounds N-(2,4-dichlorobenzylidene)-4-methylbenzohydrazide monohydrate (1) and 2-chloro-5-nitro-N-(4-methylbenzylidene)benzohydrazide (2) derived from 4-methylbenzohydrazide with different benzaldehydes are synthesized and characterized by physicochemical methods and single crystal X-ray diffraction. <...> The crystals of the compounds are stabilized by intermolecular hydrogen bonds as well as stacking interactions. <...> Hydrazides and hydrazones are nowadays of considerable technical and commercial importance due to their wide usage as drugs in medicine and as versatile ligands in coordination chemistry [ 1— 4 ]. <...> In order to carefully study the detailed structures of such compounds, in the present work, two new hydrazone compounds N-(2,4-dichlorobenzylidene)-4-methylbenzohydrazide monohydrate (1) and 2-chloro-5-nitro-N-(4-methylbenzylidene)benzohydrazide (2) (Scheme 1), derived from 4-methylbenzohydrazide with different aldehydes, were synthesized and structurally characterized. <...> Materials and methods. 4-Methylbenzohydrazide, 2,4-dichlorobenzaldehyde, and 2-chloro-5-nitrobenzaldehyde were obtained from TCI. <...> The other chemicals were used as commercially received without further purification. <...> The composition and the structures of the compounds © Lei Y., Chen G., Yang Q., Fu C., Pan J., Li T., 2013 784 have been confirmed by means of elemental analysis, 1H NMR, IR spectroscopy and single crystal X-ray diffraction. <...> Elemental analyses (C, H, and N) were performed on a Carlo Erba instruments CHNS-O EA 1108 automatic equipment. <...> The 1H NMR spectra were measured on a Varian 200 XL instrument. <...> Yellowish single crystals of the compound were obtained by recrystallization of the compound in methanol. <...> Compound 2 was synthesized and crystallized according to the same method as that described for 1, with 2,4-dichlorobenzaldehyde replaced by 2-chloro-5-nitrobenzaldehyde (1.9 g, 0.01 mol). <...> Single crystals suitable for X-ray <...>