Preparation and properties of 1-adamantoxides, 2-adamantoxides, and 1-adamantylmethoxides of Ti IV , V IV , Nb IV , Nb V , Cr III , Cr IV , Mo IV , Mn II , Fe III , and Co II . The crystal and molecular structure of tetrakis(1-adamantoxo)dimethylaminemolybdenum(IV)

Abstract

Preparation and Properties of I -Adamantoxides, 2-Adamantoxides, and I -Adamantylmethoxides of Ti'", Vlv, N biV, N bV, Crlll, Crtv, MoiV, Mn", Felli, and Co! The Crystal and Molecular Structure of Tetrakis-(1 -adamantoxo)d imet hylaminemolybden u m( iv) t* 1:

A Rare Example of Four-Coordinate Nonoxido Vanadium(IV) Alkoxide in the Solid State: Structure, Spectroscopy, and Magnetization Dynamics

“…In spite of being a metal alkoxide complex, 1 is remarkably resistant to hydrolysis, even when exposed to atmospheric moisture for long time periods. In Figure S1b, for example, a sample of microcrystalline 1 shows no changes in its characteristic vibrational (FTIR) spectrumapart from moisture incorporationafter exposition to the air for up to 6 h. The most diagnostic IR absorptions in Figure S1a have been attributed to the characteristic ν­(C–O) vibration of alkoxides at 1101, 1070, 978, and 945 cm –1 , which compare well with those of the parent 1-adamantanol molecule, and to ν­(V–O) at 689, 640, and 501 cm –1 . , The absence of an additional, strong absorption band related to the stretching mode of the VO moiety in the range of 910–1000 cm –1 , usually observed in mononuclear oxidovanadium­(IV) complexes, − supports the formation of a “bare” vanadium­(IV) species as confirmed by single crystal X-ray diffraction analysis (vide infra).…”

“…Bochmann and co-workers described the synthesis of a number of adamantyl-containing metal alkoxides, starting mainly from dialkylamide precursors . In their work, the 1-adamantoxide ligand was reported to form a mononuclear homoleptic complex with the “bare” vanadium­(IV) cation, but no crystal structure analysis was described for this product. The only reported compound characterized by the authors by X-ray crystallography was a heteroleptic molybdenum­(IV) complex.…”

“…Whereas other tertiary alkoxides, such as tert -butoxide and tert -pentoxide, are known to form mononuclear products with nonoxido vanadium­(IV) that are liquid at room temperature, , the 1-adamantoxide ligand gives a crystalline blue solid . This feature makes the [V­(OAd) 4 ] complex interesting for detailed studies of the simple tetracoordinate vanadium­(IV) unit through techniques that can be useful for the characterization of solid products.…”

“…This is mainly due to the high electron deficiency of these species, which tends to favor polynuclear aggregation. Inspired by an early report from Bochmann and Wilkinson, we here report the synthesis of a mononuclear vanadium-adamantyl complex, [V­(OAd) 4 ] ( − OAd = 1-adamantoxide, complex 1 ), by a different route with respect to that previously described. To the best of our knowledge, 1 represents the first homoleptic, “bare” V IV alkoxide confirmed to be mononuclear and nearly tetrahedral, at room or higher temperature, by single-crystal X-ray diffraction analysis.…”

Inhibition of Alkali Metal Reduction of 1‐Adamantanol by London Dispersion Effects

“…[4a,b] One way of installing many van der Waals (vdW) forces experimentally to effect dispersion stabilization is through the addition of multiple CÀ H moieties within a ligand framework, especially of rigid organic groups. [5] The 1adamantoxide (OAd 1 ) ligand has been investigated previously for a range of transition-metal complexes, owing to their kinetic and thermally stabilizing properties, [6][7][8][9] nonetheless the LD contributions of these ligands were generally not discussed. The OAd 1 ligand was also employed in studies of unusual zinc complexes, which despite the moderate bulk of the 1-adamantyl unit, [10] afforded a [RZn-(OAd 1 )] 4 , R =À CH 2 (SiMe 3 ) tetrameric cubane-structure, featuring many intramolecular (but unremarked upon) close-contacts between C•••H and H•••H atoms of the adamantyl and trimethylsilyl groups.…”