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 M 4L 4-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. © 2012 American Chemical Society.