Scandium tropolone

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... 

Scandium is more like an element of the first transition series (or like aluminum) than like the rare earths. For example, it characteristically has a coordination number of 6 (6-coordinate radius, 0.89 A compared to 1.00-1.17 A for the lanthanides), although coordination numbers 8 and 9 are known. Examples of CN 8 are Na5[Sc(C03)4] -6H20 and the tropolonate, [SeT4] . There is but one example of CN 9, namely the tricapped trigonal prismatic [Sc(H20)9]3+ ion found in Sc(CF3S03)3-9H20.38 The aqua ion in solution, [Sc(H20)6]3+, is appreciably hydrolyzed and OH-bridged di- and trinuclear species are formed. 

Since the determination of the structure of tris(acetylacetonato)scandium (Sc—O of 2.061-2.082 A, average Sc—O 2.070(9) A), several other diketonates have been examined, though no detailed structures have been reported. The compound mer-[Sc(CF3COCHCOCH3)3] is isostruc-tural with the aluminium, gallium, rhodium, and iridium analogues, as well as those of the 3d metals V-Co whilst the dipivaloylmethanide [Sc(Me3COCHCOMe3)3] is isostructural with the iron and indium analogues. Scandium a-diketonates such as [Sc(tropolonate)3] form adducts in... 

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