Synthesis and crystal structure of a triple-decker (Cu3Tl2I)-Tl-II complex: first example of a thallium(I) system in the imino-phenolate Schiff base ligand family

This report deals with the synthesis, characterization, and crystal structure of a heteropentanuclear (Cu3Tl2I)-Tl-II compound [((CuL)-L-II)(3)Tl-2(I)](NO3)(2) (1), where H2L=N,N '-ethylenebis(3-ethoxysalicylaldimine). This compound crystallizes in the monoclinic crystal system within space group C2/c. Each of the two symmetry related thallium(I) centers is located between a terminal and a common, central [(CuL)-L-II] by forming bonds with four phenoxo and three ethoxy oxygens. The three [(CuL)-L-II] moieties are parallel and hence 1 is a triple-decker system. Neighboring triple-decker moieties are interlinked by pi MIDLINE HORIZONTAL ELLIPSIS pi stacking interaction and weak hydrogen bonds to generate 3-D self-assembly in 1. Salient features in the composition and structure of the title compound are discussed; the title compound is the first example of a thallium(I) system in imino-phenolate Schiff base family.