Alkyl scandium complexes coordinated by dianionic O,N,N- and O,N,O-ligands derived from Schiff bases

The reactions of imino phenols 3,5-Bu^t₂-2-HOC₆H₂CH=NX (X = 8-C₉H₆N, 2-MeO-5-MeC₆H₃ and 2-PhOC₆H₄) with Sc(CH₂SiMe₃)₃(THF)₂ in toluene proceed with silane elimination and reductive alkylation of the C=N group affording dimeric base-free monoalkyl scandium complexes. X-ray analysis of the two complexes revealed their dimeric structures due to μ-bridging amidophenolato dianions. The complexes catalyze hydrophosphination of styrene, phenylacetylene and tolane with Ph₂PH as well as dehydrogenative coupling of anisole with hydrosilanes.