Zinc ethoxide

Contact of the neat liquids with uncooled methanol is explosively violent and leads to ignition. For analysis, ampouled samples of dialkylzincs must first be frozen in liquid nitrogen before being broken under methanol-heptane mixtures at — 60°C. See Zinc ethoxide Nitric acid... 

Tetrakis(ethylthio)uranium, 3096 Titanium butoxide, 3730 Titanium(III) methoxide, 1317 Titanium tetraisopropoxide, 3579 Tungsten hexamethoxide, 2604 Zinc ethoxide, 1704... 

Zinc oxide is a semiconducting ceramic used to make varistors (variable resistors). Write a balanced equation for the hydrolysis of zinc ethoxide in the sol-gel method for making ZnO powders. 

Dibutylzinc, 3074 Diethylzinc, 1712 Diisobutylzinc, 3075 Diisopentylzinc, 3365 Dimethylzinc, 0931 Dipropylzinc, 2546 See Zinc ethoxide Nitric acid See other ALKYLMETALS... 

Tetrakis(ethylthio)uranium, 3090 Titanium butoxide, 3724 Titanium tetraisopropoxide, 3573 Titanium(III) methoxide, 1313 Tungsten hexamethoxide, 2600 Zinc ethoxide, 1698... 

Furukawa et al. [274] and Natta cl al. [275,276] succeeded independently in the preparation of crystalline polyacetaldehyde by using some organometallic compounds, such as diethylzinc or triethylaluminium, for the low-temperature polymerisation of acetaldehyde. Metal alkyls and metal alkoxides, e.g. aluminium isopropoxide, zinc ethoxide or ethyl orthotitanate, have also polymerised other aldehydes such as propionaldehyde and trichloroacetaldehyde to give crystalline polymers (Table 9.3) [270,275,277], A highly crystalline isotactic polymer has been obtained from the polymerisation of w-butyraldehyde with triethylaluminium or titanium tetrachloride-triethylaluminium (1 3) catalysts. Combinations of metal alkyl, e.g. diethylzinc, with water [278] or amine [279] appeared to give very efficient catalysts for aldehyde polymerisations. 

Deprotonation of the zinc alcohol complexes shown in Fig. 12 to produce zinc alkoxide species has not been reported. Instead, mononuclear, tetrahedral zinc alkoxide complexes, supported by hydrotris(pyrazolyl)borate ligands, ([TpBut,Me or Tpph,Me, Scheme 8), have been generated via treatment of zinc hydride precursor complexes with aliphatic alcohols.68-70 A zinc ethoxide complex, [TpBut,Me]Zn-OEt, was also prepared via decarboxylation of the ethyl carbonate complex, [TpBut,Me]Zn-0C(0)0Et.49 X-ray crystallographic studies of [Tpph Me] Zn-OCH3 and [TpBut,Me]Zn-OEt revealed Zn-O bond lengths of 1.874(2) and 1.826(2) A, respectively.68,71 These bond distances are 0.1 A shorter than found for the alcohol complexes shown in Fig. 12. 

In a model reaction for liver alcohol dehydrogenase, the zinc ethoxide complex [TpBut,Me]Zn-OEt reacts stoichiometrically with -nitrobenzaldehyde in benzene to produce [TpBut,Me]Zn-0CH2C6H4N02 and acetaldehyde (Scheme 10).68 For a series of similar reactions involving the zinc isopropoxide complex [Tpph,Me]Zn-OCH(CH3)2 and various aromatic aldehydes in toluene (Scheme 10), the zinc-containing products of the reaction, [Tpph,Me]Zn-OCH2Ar, were isolated in 60-70% yield, while the acetone produced was identified using ]H NMR.70... 

Fandrick et al. used the same strategy to form a catalyst in situ for the preparation of zinc ethoxide from diethyl zinc and ethanol, to catalyze allylation of a wide range of ketones by allyl pinacol boronate, 122 (reaction 7.26) with over 90% yield [76]. 

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