274266-77-2Relevant academic research and scientific papers
Self-assembled macrocyclic tetranuclear molecular square [Ni(HL)]44+ and molecular rectangle [Cu2Cl2L]2 {H2L = bis[phenyl(2-pyridyl)methanone] thiocarbazone}
Cheng, He,Chun-ying, Duan,Chen-jie, Fang,Yong-jiang, Liu,Qing-jin, Meng
, p. 1207 - 1212 (2000)
The conformationally rigid, nickel(n)-based cationic molecular square [Ni(HL)]44+ and copper(n)-based neutral molecular rectangle [CujCljLjj were achieved via self-assembly from novel rigid pentadentate N4S ligand bis[phenyl(2-pyridyl)methanone] thiocarbazone(H2L). Crystal structure analyses show that the tetranuclear nickel(n) cation [Ni(HL)]44+ is located at the inversion center with four nickel atoms in the corners of a square with edge length Ni ... Ni ca. 4.8 A, each metal center being octahedrally coordinated by sulfur atoms, pyridine nitrogen and carbazone nitrogen atoms from two perpendicular HL~ ligands. Relative to the square of metal cations the sulfur atoms are midway between the edges of the square, each being connected to two nickel atoms with the angles Ni-S-Ni ca. 163°. The tetranuclear copper(n) complex [Cu2Cl2L]2 is also located in the inversion center with four copper atoms in the corners of a rectangle. Two edges of the rectangle are Cu-S-Cu bridges with edge length Cu ... Cu of 4.51 A, the other two edges are double Cu-Cl-Cu bridges with Cu ... Cu distance of 3.41 A. Each metal center is coordinated in a tetragonal-pyramid with the sulfur atom, pyridine nitrogen atom, carbazone nitrogen atom and one chlorine atom comprising the basal plane, whereas the other chlorine atom of the symmetry-related half of the molecule occupies the apical position. The crystal structure of the free ligand is also reported for comparison. The Royal Society of Chemistry 2000.
