Stannates organic

The reaction is reversible (equation 3, step a) and, furthermore, a mixture of stannate complexes may undergo disproportionation to establish an equilibrium between homo-and mixed-ligand compounds (equation 3, step b). Moreover, the aryloxy mixed ligand stannates 36-38 are more stable than a 1 1 mixture of the corresponding dichloro- and bis(aryloxy)-stannates. Thus, the stability of the TAS stannates with TBP structures is highly affected by the nature of the equatorial organic groups and apical heteroatom substituents. 

Tin, having valence of +2 and +4, forms stannous (tin(II)) compounds and stannic (tin(IV)) compounds. Tin compounds include inorganic tin(II) and tin(IV) compounds complex stannites, MSnX3, and stannates, M2SnX5, and coordination complexes, organic tin salts where the tin is not bonded through carbon, and organotin compounds, which contain one-to-four carbon atoms bonded direcdy to tin. 

Stannane (SnH4) is obtained by interaction of SnCl4 and LiAlHi in ether at -30°C. It decomposes rapidly when heated and yields j8-tin at 0°C. Although it is stable to dilute adds and bases, 2.5 M NaOH causes decomposition to Sn and some stannate. Stannane is easily oxidized and can be used to reduce organic compounds (e.g., QHsCHO to CfH5CH2OH, and C6H5N02 to Cf,H5NH2). With concentrated... 

The hydrostannolysis of organic halides was discovered when an attempt at the hydro-stannation of allyl bromide resulted instead in hydrodebromination.37... 

Cadmium stannate, used as electrodes in photogalvanic cells, is another example of a transparent conductor oxide (TCO) having desirable properties, such as good durability and chemical resistance. It can be produced by the spray pyrolysis CVD method with organic solutions of CdCH and SnCH or [Cd(hfa)2 (TMEDA)] and [Sn(acac)2]. ° It also shows the unexpected effect of improving transparency with increasing Him conductivity higher than tin-doped indium oxide. 

There are several fillers and inoiganic/organic additives used in flame retarded materials and these include antimony oxide, aluminum trihydrate, zinc borate, ammonium octamolybdate, and zinc stannate. The details related to the composition required and performance characteristics of inorganic additives can be found in specialized monograph. Some of these compounds are discussed below in relation to their effects on enhancement of performance of phosphate plasticizers. 

Apart from organic derivatives, compounds containing tin—tin bonds are generally very unstable. Distannane, Sn H, is formed in low yield, together with stannane, SnH, by reduction of aqueous alkaline stannate(II) solutions with sodium borohydride. The preparation of Sn Cl has been claimed, but it disproportionates to SnCl and SnCl even at — 65°C. 

Furlani, D. Marton, D. Tagliavini, G., Zordan, M. (1988) Hydrated a-bonded organometallic cations in organic synthesis. I. Allyl-, crotyl-, 1-methylallyl-, cyclohex-2-enyl-, and cinnamyl-stannation of carbonyl compounds in water, J. Organomet. Chem., 341,345-56. 

In the presence of a nucleophile like a bromide ion, stannyl enol ethers are converted into anionic pentacoordinate stannates, which nucleophilically react with organic halides to give or-alkylated carbonyl compounds. In contrast, such penta-coordinated tin species hardly react with carbonyl electrophiles. The higher coordinated species is also generated by treatment of tin(IV) enol ethers with not only Bu4NBr but an aprotic polar solvent like Such pentacoordinate stannates add in a similar... 

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