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The electrochemical synthesis of Sc(OMe)3 (1), Sc(OEt)3 (2) and Sc5O(OPri)13 (3) was carried out via anodic oxidation of scandium metal in aliphatic alcohols. X-ray single crystal study showed 3 to be analogous to the known isopropoxides of Y, Er, Yb and In. The interaction of 3 with excess ROH (R=Me, Et, Bun, Bus, But) gives non-volatile amorphous 1, 2 and Sc(OBun)3 (4), and volatile Sc5O(OBus)13 (5) and Sc5O(OPri)8(OBut)5 (6). Oxoalkoxides Sc5O(OPri)8(OR)5 (R=Bun 7, Me 8) were obtained on reaction of 3 with n-ROH in 1:5 ratio. The mass spectral study shows 5 is an individual compound, whereas 6–8 in the gas phase consist of a number of aggregates with different extents of substitution for OPri groups, Sc5O(OR)n(OPri)13−n: for R=But n≤5, for R=Bun n≤8, and for R=Me n≤12. The maximal intensity in the spectrum of 6 is observed for Sc5O(OPri)10(OBut)2+, and in the spectra of 7 and 8 for Sc5O(OPri)12−n(OBun)n+, n=4, 5, and Sc5O(OPri)9(OMe)3+ respectively. The presence of the Sc5O(OMe)12+ ion in the spectrum of 8 indicates the possibility of replacing all the OPri in the pentanuclear core and demonstrates the existence of a ‘volatile scandium methoxide’ in the gas phase. Study of the complex formation of Sc(OR)3 with Al(OR)3 has shown that 2 and 4 form volatile Sc[Al(OR)4]3, R=Et 9, Bun 10, while 3 does not react under these conditions. Sc[Al(OPri)4]3 (11) can be obtained only on exchange reaction of ScCl3 with KAl(OPri)4. The results obtained indicate rather high stability of the [Sc5O(OR)8] core for primary and secondary R.

Reactions of the [K]+ salts of the [nido-7,9-C2B9H12]- anion (2) and its C-phenylated derivative [7-Ph-nido-7,9-C2B9H11]- (4) with [OsCl2(PPh3)3] (3) proceed in benzene at ambient temperature with the formation of 16-electron chlorohydrido-Os(IV) exo-nido complexes, [exo-nido-10,11-{(Ph3P)2OsHCl}-10,11-(mu-H)2-7-R-7,9-C2B9H8] (5: R = H; 6: R = Ph), along with the small amounts of the charge-compensated nido-carboranes [nido-7,9-C2B9H11PPh3] (7) and [7-Ph-nido-7,9-C2B9H10PPh3] (8) as byproducts. However, when carried out under mild heating in ethanol, the reaction of 2 with 3 selectively afforded a 16-electron dihydrido-Os(IV) exo-nido complex [exo-nido-10,11-{(Ph3P)2OsH2}-10,11-(mu-H)2-7,9-C2B9H9] (9). Structures of both complexes 5 and 9 have been confirmed by single-crystal X-ray diffraction studies, which revealed that nido-carboranes in these species function as a bidentate dicarbollide ligands [7-R-nido-7,9-C2B9H10]2- linked to the Os(IV) center via two B-H...Os bonds involving adjacent B-H vertices in the upper CBCBB belt of the carborane cage. Thus, compounds 5 and 9 represent the first structurally characterized exo-nido-metallacarboranes based on meta-dicarbollide-type ligands. Variable-temperature 1H and 31P{1H} NMR experiments indicate that complex 9 is fluxional in solution and shows an unusual exchange between terminal Os-(H)2 and bridging {B-H}2...Os hydrogen atoms. Upon heating in d8-THF at 65 degrees C, complex 9 converts irreversibly to its closo isomer [2,2-(PPh3)2-2,2-H2-closo-2,1,7-OsC2B9H11] (13), which could thus be obtained as a pure crystalline solid. The structure of 13 has been established on the basis of analytical and multinuclear NMR data and a single-crystal X-ray diffraction study.

The hexanuclear complex of calcium oxo ethoxide ethanol solvate, [Ca6O2(OEt)8]·14EtOH 1 has been isolated after the prolonged refluxing of an ethanol solution of calcium ethoxide in the presence of the oxygen in air and studied by X-ray diffraction; the metal-oxygen framework is built of two [Ca4O4] cubes sharing a common [Ca2O2] face, which involves both oxo groups.