Synthesis and Solid-State X-ray Structure of the Mononuclear Palladium(II) Complex Based on 1,2,3-Triazole Ligand

Abstract

Herein, we described the synthesis and X-ray crystal structure of the new [Pd(3)2Cl2] complex with 1,2,3-triazole-based ligand (3). In the unit cell, there are two [Pd(3)2Cl2] molecules, and the asymmetric unit comprised half of this formula due to the presence of an inversion symmetry element at the Pd(II) center. The monoclinic unit cell volume is 1327.85(6) Å3, with crystal parameters of a = 10.7712(2) Å, b = 6.8500(2) Å, and c = 18.2136(6) Å, while β = 98.851(2)°. The structure comprised two trans triazole ligand units coordinated to the Pd(II) ion via one of the N-atoms of the triazole moiety. In addition, the Pd(II) is further coordinated with two trans chloride groups, where each of the trans bonds is equidistant. The crystal structure of the [Pd(3)2Cl2] complex was compared with that for free triazole ligand 3. It was found that the coordinated ligand showed less twist around the C–N bond compared to free triazole ligand 3. The molecular packing of the latter is found controlled by short O…H, N…H, C…N, and C…C interactions in addition to the short Cl…F interhalogen and π–π interactions. H…H (23.5%), Cl…H (14.4%), N…H (14.3%), and O…H (11.2%) are the most dominant contacts. In the [Pd(3)2Cl2] complex, no significant interhalogen or π–π interactions were detected. In this case, Cl…H (31.1%), H…H (16.7%), O…H (11.6%), and F…H (9.7%) are the most dominant contacts.