Self-assembly of Thiolato-Bridged Manganese(I)-Based Metallarectangles: One-pot Synthesis and Structural Characterization

A new series of thiolato-bridged manganese­(I)-based supramolecular rectangles have been achieved by three-precursor self-assembly of Mn₂(CO)₁₀, diaryl disulfides (RSSR), and linear ditopic azine ligands (L) [L = pyrazine (pz), 4,4′-bipyridine (bpy), and trans-1,2-bis­(4-pyridyl)­ethylene (bpe)] using a one-pot synthetic strategy. Oxidative addition of RSSR (diphenyl disulfide and p-tolyl disulfide) to manganese decacarbonyl in the presence of rigid bidentate ligands (L) afforded metallarectangles of the general formula [{(CO)₃Mn­(μ-SR)₂Mn­(CO)₃}₂(μ-L)₂] (1–6). Compounds 1–6 were characterized using elemental analyses and NMR, IR, and UV–vis absorption spectroscopic techniques. The molecular structures of metallarectangles 1, 3, and 5 were elucidated by single-crystal X-ray diffraction methods. The guest binding ability of 3 and 5 has been investigated with two aromatic guests using electronic absorption and fluorescence emission spectroscopy, and the results revealed a strong binding interaction between host–guest species.