Scandium aryloxides

Scandium, tetrakis(tropolone)-stereochemistry, 1,94 Scandium, tris(acetylacetone)-structure, 1. 65, 68 Scandium, tris(tropolonate)-structure, 1,68 Scandium aryloxides spectroscopy, 2, 346 Scandium chloride... 

Furthermore, these bulky aryloxide ligands played a crucial role in making the crystallographically characterized less-familiar three-coordinate compounds of scandium, yttrium, and the lanthanides (Ln), such as Ln(OC6H2-r-Bu2-2,6-R-4)3 (28) more accessible. 

The syntheses, physical properties, and molecular structures of alkoxides and aryloxides have been discussed in CCC (1987).161 The alkoxides of scandium and yttrium were reviewed in CCC (1987).1 There have been more recent developments in this area and the impetus for this chemistry has been the developments in materials research. Metal alkoxides and /3-diketonates can be used as precursors for oxide and nonoxide thin films.162 The stable M—O bond and the volatility of the metal alkoxides are important features of this area of chemistry. This has lead to more research in this area particularly in synthesis, NMR, and X-ray crystallography. 

Hitchcock, P. B., Lappert, M. P., and Singh, A., Three and four-co-ordinate hydrocarbon-soluble aryloxides of scandium, yttrium and the lanthanides X-ray crystal structure of tris(2,6-di-t-butyl-4-methylphenoxo)scandium, J. Chem. Soc. Chem. Commun., 1499 (1983). 

The monomeric three-coordinate aryloxides of scandium and titanium, M(OAr >3 (OAr = 2,6-di-t-butylphenoxide), have been reported. The electronic and ESR spectra of deep blue Ti(OAr )3 are consistent with a trigonal planar geometry and a strong Ti(OAr ) ion was observed in the mass spectrum. "... 

Asymmetric 1,3-dipolar cycloaddition reaction of AT-benzylidenebenzyl-amine AT-oxide to 3-(( )-2-butenoyl)-l,3-oxazolidin-2-one was catalyzed by BlNOL-BOX-scandium complexes to give isoxazolidine in high yield with high enantioselectivity (111). La(lll)-aryloxide-PYBOX complexes were reported as enantioselective catalysts for direct Mannich-type reactions (112). 

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