2D and 3D supramolecular assemblies of double cyclopalladated azobenzenes realized by C–H⋯Cl–Pd, π⋯π and C–H⋯π interactions

The double cyclopalladated complex with azobenzene, μ-[(E)-1,2-diphenyldiazene-C2,8, N1,2]-di-[chloro(dimethylsulfoxide)palladium(II)]; (DMSO)PdCl(μ-C6H4NNC6H4)(DMSO)PdCl (1) and its analogous complex with DMF as ancillary ligand, (DMF)PdCl(μ-C6H4NNC6H4)(DMF)PdCl; μ-[(E)-1,2-diphenyldiazene-C2,8,N1,2]-di-[chloro(dimethylformamide)palladium(II)] (2a) were synthesized and the function of cyclopalladated moiety in molecular assembling in the solid state is illustrated by their crystal packings. The polymorphism of 2a and 2b is discussed. The crystal structures reveal assemblies with molecular components self-organized by C–H⋯Cl–Pd hydrogen bonds, π⋯π, and C–H⋯π interactions. The double cyclopalladated complexes of azobenzene, with two Pd–Cl moieties participating in the hydrogen bond formation and π-conjugated system involved in the π⋯π or C–H⋯π interactions, represent a new class of building blocks for construction of solid state supramolecular assemblies.

Graphical abstractThe crystal structures of the double cyclopalladated complexes with azobenzene are two- and three-dimensional arrays in which molecular components are self-organized through C–H⋯Cl–Pd hydrogen bonds and π⋯π or C–H⋯π interactions. These complexes, with two Pd–Cl bonds participating in the hydrogen bond formation and π-conjugated system involved in the π⋯π or C–H⋯π interactions, represent a new class of building blocks for construction of solid state supramolecular assemblies.Figure optionsDownload full-size imageDownload as PowerPoint slide