Metal alkoxides interactions between

Addition of potassium ferf-butoxide or of sodium isopropoxide to the solvent led to ignition of the latter. This was attributed to presence of free metal in the alkoxides, but a more likely explanation seems to be that of direct interaction between the powerful bases and the sulfoxide. 

Although phenyl-sodium and -potassium may be made from reactions between phenyl-lithium and the heavier metal alkoxides, the structures of the donor-free solid compounds are apparently still unknown. The dimeric adducts [NaPh.PMDTA]2 and [NaC6H4Ph.TMEDA]2 have been characterized1 and the structure of a solvent-free arylsodium [Na(C6H3Mes2-2,6)]2, 32 (Fig. 17), has been described.63 The sodium interacts with the ipso... 

In the case of the alkoxides and phenoxides of molybdenum(III) the interaction between metal atoms becomes dominant, leading to diamagnetic compounds of stoichiometry Mo2(OR)6 or Mo4(OR )i2(R/ = the less bulky Me or Et).78 These compounds are readily sublimable, (70-90 °C/ 10-3 Torr for Mo OPr1 ) and retain either their dimeric or tetrameric nature both in solution and the gas phase, as determined by cryoscopic measurements and mass spectrometry, respectively.78 An analogous tungsten(III) complex W2(OBu )6 can be obtained, but for other alkoxides the simple homoleptic compounds cannot be isolated.79,168... 

Oppenauer oxidation, using alkoxides other than aluminium, operates via a hydride transfer mechanism similar to the one depicted in the above Equation, although a complexation of the metal with the carbonyl group may not be present.22d Evidence for a radical mechanism was put forward in the case of the interaction between lithium isopropoxide and benzophenone.24... 

The interaction of the metal alkoxides with the salts of carboxylic acids or with p-diketonates of other metals is especially attractive for the synthesis of bimetallic molecular precursors in the cases, when the preparation of the alkoxide of the other metal is somehow hindered or it is insoluble or irreactive under the conditions applied. This method has been widely used for the sol-gel preparation of HTSC materials (because of low solubility and reactivity of Cu(OR)2) and lead-containing ferroelectrics (in the view of difficult synthesis and low stability of Pb(OR)2). It should be mentioned that the reaction between a metal alkoxide and a functional derivative does far not always lead to the formation of a mixed-ligand bimetallic complex ... 

Asymmetric hydroboration of ketones with catecholborane in the presence of 0.02-0.025 equivalents of (R,R)-8, which was prepared from LiGaH4 and 2 equivalents of 2-hydroxy-2 -mercapto-l,r-binaphthyl, afforded the corresponding alcohols in a high yield and with high enantioselectivity (Scheme 6) [46]. The solid-state structure of 8 is drawn in this scheme. The preferential interaction between soft Ga metal and soft thiolate is supposed to prevent the replacement of the chiral ligand by the alkoxide product. 

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