Self-Assembly of Manganese(I)-Based Molecular Squares: Synthesis and Spectroscopic and Structural Characterization

Syntheses of manganese­(I)-based molecular squares have been accomplished in facile one-pot reaction conditions at room temperature. Self-assembly of eight components has resulted in the formation of M4L4-type metallacyclophanes [Mn­(CO)3Br­(μ-L)]4 (1–3) using pentacarbonylbromomanganese as metal precursor and rigid azine ligands such as pyrazine, 4,4′-bipyridine, and trans-1,2-bis­(4-pyridyl)­ethylene, respectively, as bridging ligands. The metallacyclophanes have been characterized on the basis of IR, NMR, and UV–vis spectroscopic techniques and single-crystal X-ray diffraction methods.