Structures of Protonated Bis(pyridine-2-yl) Ketone Arylhydrazone Derivatives: [(C 5 H 4 N)(C 5 H 4 NH)C=NNHC 6 H 4 Y] + [X] − (Y,X = 3-O 2 N,Cl: 4-Me,Cl:)

The crystal structures of two salts of protonated bis(pyridine-2-yl) ketone arylhydrazone derivatives, [(C 5 H 4 N)(C 5 H 4 NH)C=NNHC 6 H 4 Y] + [X] − , 2 (Y,X = 3-O 2 N,Cl), and the trihydrate of 3 (X,Y = 4-Me,Cl), are reported from data collected at 120 K. The cations in 2 and 3 exhibit different conformations, which have consequences in the type and number of intra- and intermolecular interactions exhibited. Three dimensional arrays are generated for both compounds by different combinations of intermolecular interactions. In 2 , the cations are linked directly by π−π stacking interactions and by C−H···O hydrogen bonds, as well as by bridging chloride ions. The cations in [( 3) ·3H 2 O] are directly again linked by π−π stacking and also by C−H···π interactions, and indirectly via chloride ions and water molecules. Compound 2 crystallises in the monoclinic space group P 21/ c , with a = 14.4210(4) Å, b = 9.1543(3) Å, c = 12.3365(3) Å, β, 104.583(2) o and Z = 4. Compound 3 crystallises in the triclinic space group P -1, with a = 8.1352(2) Å, b = 10.0278(3) Å, c = 12.1482(4) Å, α = 106.4290(14) o , β = 92.8080(18) o , 90.3920(18) o , Z = 2. Graphical Abstract [Different three dimensional arrays are generated by different combinations of intermolecular interactions in [(C 5 H 4 N)(C 5 H 4 NH)C = NNHC 6 H 4 Y] + [X] − , 2 (Y,X = 3-O 2 N,Cl), and the trihydrate of 3 (X,Y = 4-Me, Cl.] .