Reduction of Diphenylacetylene Mediated by Rare-Earth Ferrocene Diamide Complexes

The synthesis and characterization of Ln-C4Ph4-K, [(NNTBS)­Ln­(η2-C4Ph4)]­[K­(THF)x] (Ln = Sc, Y, Lu), rare-earth metal complexes supported by a ferrocene diamide ligand, NNTBS (NNTBS = fc­(NSitBuMe2)2, fc = 1,1′-ferrocenediyl), were accomplished. The preparation of the half-sandwich compounds, Ln-naph-K, [(NNTBS)­Ln­(μ-C10H8)]­[K­(THF)2] (Ln = Sc, Y, Lu, La), was necessary in order to obtain high yields of rare-earth metallacyclopentadienes. Unlike Y and Lu, La did not show the same reactivity toward PhCCPh. The characterization of the new metal complexes was accomplished by NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction.