N′-[Bis(benzylsulfanyl)methylidene]-4-methoxybenzohydrazide

In the title compound, C23H22N2O2S2, the dihedral angles between the 4-methoxy-substituted phenyl ring and the other two phenyl rings are 84.4 (4) and 77.7 (1)°, respectively, while the dihedral angle between the two phenyl rings is 57.5 (2)°. The amino group is not involved in an N—H hydrogen bond. The crystal packing is established by intermolecular C—H⋯O packing interactions involving a relatively rare weak three-center hydrogen bond between the keto O atom and H atoms of the two nearby phenyl rings, which link the molecules into chains running along the a axis. Additional weak intermolecular hydrogen-bond interactions between the 4-methoxy O atom and one of the phenyl rings and provide added stability to the crystal packing.

In the title compound, C 23 H 22 N 2 O 2 S 2 , the dihedral angles between the 4-methoxy-substituted phenyl ring and the other two phenyl rings are 84.4 (4) and 77.7 (1) , respectively, while the dihedral angle between the two phenyl rings is 57.5 (2) . The amino group is not involved in an N-H hydrogen bond. The crystal packing is established by intermolecular C-HÁ Á ÁO packing interactions involving a relatively rare weak three-center hydrogen bond between the keto O atom and H atoms of the two nearby phenyl rings, which link the molecules into chains running along the a axis. Additional weak intermolecular hydrogen-bond interactions between the 4methoxy O atom and one of the phenyl rings and provide added stability to the crystal packing.
The sum of the angles around C1 (120.00 (8)°) and the S1A/C1/S1B bond angle of 117.52 (7)° indicated nearly planar sp 2 hybridized behavior (Fig. 1). The molecule can be divided into three distinct fragments with regard to their spatial orientation viz keto-amide, 4-methoxy benzene and bis benzyl sulfanyl methylene groups. Regarding the keto-amide group, all three rings including the 4-methoxy benzene, and two separate benzyl rings A relatively rare weak three-center hydrogen bond configuration and additional weak C-H···O donor hydrogen bonds can be seen linking the molecules into chains along the (011) plane (Fig. 2). Additional hydrogen bonds between the 4-methoxy oxygen atom (O2) and one of the benzyl groups (C6B-H6BA···O2) help to stabilize crystal packing.

Experimental
The potassium salt of N'-(4-methoxy benzoyl) hydrazine carbodithioate was prepared by adding carbon disulfide (0.04 mol, 2.4 ml) to a solution of 4-methoxy benzoic acid hydrazide(0.02 mol, 3.32 g) and potassium hydroxide (0.02 mol, 1.12 g) in methanol (30 ml) then stirring the reaction mixture for 2 h. The solid separated was filtered off, washed with 10% (v/v) mixture of ethanol-ether and dried in vacuo. Yield 1.54 g, 55%, m.p. 518 K. The title compound was prepared by drop wise addition of benzyl chloride (0.02 mol, 2.53 g) to a suspension of potassium salt of N'-(4-methoxy benzoyl)hydrazine carbodithioate (0.01 mol, 2.80 g) in methanol (20 ml) and stirring the reaction mixture for a period of 5-6 h. The reaction mixture was filtered and the solution was evaporated almost to dryness. The solid was washed several times with carbon supplementary materials sup-2 tetrachloride and then with chloroform and recrystallized from methanol. Transparent white shining crystals of (I) (m.p. 475 K), suitable for X-ray analysis were obtained by slow evaporation of the methanol solution over a period of 9-10 days (yield 2.53 g, 60%): Anal Calcd (%): C,65.31;H,5.20;N,6.62;S,15.17;Found(%)

Refinement
All of the H atoms were placed in their calculated positions and then refined using the riding model with C-H = 0.95-0.99 Å, N-H = 0.88\|A%, with U iso (H) = 1.18-1.49U eq (C) and U iso (H) = 1.19U eq (N).

Special details
Experimental. Refinement. Refinement on F 2 against ALL reflections. Weighted R-factors wR and all goodnesses of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.