Crystal structure of 4-hydroxy-3-methoxy-N’-(5-chloro-2-hydroxy-benzylidene) benzohydrazide—methanol (1:1), C15H13ClN2O4·CH3OH

Abstract

Source of materialThe title compound was prepared by the Schiff base condensation of equimolar (0.5 mmol each) solutions of 5-chlorosalicylaldehyde and 4-hydroxy-3-methoxybenzohydrazide in methanol (20 ml). Excess methanol was removed from the reaction mixture by distillation. The colourless solid was filtered and dried in air. Colourless block-shaped crystals suitable for X-ray diffraction were obtained from amethanol solution. Experimental detailsThe imino Hatom was located in adifference map and refined with N-H distance restrained to 0.90(1) Å.T he remaining H atoms were positioned geometrically82 Å]and refined using ariding model, with U iso (H) =1.2 U eq (C) and 1.5 U eq (C methyl and O). Rotating group models were used for the methyl groups. DiscussionHyrazone compounds, obtained from the reaction of aldehydes with hydrazides, have been widely studied due to their excellent biological properties [1][2][3]. Recently, we have reported af ew hydrazone compounds [4][5][6]. The title crystal structure consists of aSchiff base molecule and a methanol molecule. The Schiff base molecule has a trans configuration with respect to the methylidene group. The dihedral angle between the two phenyl rings is 2.5(2)°, indicating an early coplanar configuration of the molecule. The bond lengths and angles in the compound are found to have normal values and comparable to the values in the similar compounds [7][8][9]. The methanol molecules are linked to the Schiff base molecules through intraand intermolecular N−H···O and O−H···O hydrogen bonds. The molecules are linked into two-dimensional layers parallel to the bc plane by intermolecular O−H···O hydrogen bonds.