Isoproxides

Finally the hydrolysis of II gives the alcohol and regenerates aluminium isoproxide by combining with the acetone. 

Another synthetic use of the M-P-V reaction has been exploited in the synthesis of new alkoxide derivatives.247,248 Hence, 2-hydroxybenzaldehyde (salicylaldehyde) will react with isoproxides of titanium and zirconium to initially displace isopropyl alcohol and give mixed derivatives which on heating undergo reduction of the aldehyde function with elimination of acetone. The stoichiometry of the overall reaction can be represented as shown in equation (66).248... 

Bis(acctonitro)chloronitropalladium(II). /-Butyl hydroperoxide-Dialkyl taitratesr-Vanadium(IV) isoproxide. t-Butylhydroperoxide-Molybdenum carbonyl. t-Butylhydroperoxide-Vanadyl acetylacetonate. [(— )-Camphor-10-ylsulfonyl]-3-aryloxaziridines. m-Chloroperbenzoic acid-Potassium fluoride. Dimethylsulfonium methylidc. 3,5-Dinitroperbenzoic acid. Hydrogen peroxide-Vilsmeier reagent. p3-Oxohexakis(p-... 

A flask is cooled to — 20 °C and 1.24 g (6.0 mmol) of ( + )-diethyI L-tartrale and 1.49 mL (1.42 g, 5.0 mmol) of titanium(IV) isoproxide are added sequentially by syringe with stirring. The reaction mixture is stirred at — 20 °C as 39 mL (200 mmol, 5.17 M in isooctanc) of terf-butyl hydroperoxide are added through the addition funnel at a moderate rate (over ca. 5 min). The resulting mixture is stirred at — 20 °C for 30 min. 12.82 g (100 mmol) of freshly distilled ( )-2-octenol, dissolved in 50 mL of CH,C12, are then added drop-wise through the same addition funnel over a period of 20 min, being careful to maintain the reaction temperature between —20° to — 15°C. The mixture is stirred for an additional 3.5 h at —20° to —15 °C. The workup procedure as above with iron(II) sulfate solution yields the epoxy alcohol (12.6 g, 88% crude yield, 92.3% cc by GC) which upon two rccrystallizations from petroleum ether (bp 40- 60°C) at — 20°C gives the product yield 10.5 g (73%) >98% ee. 

Surface zirconium isoproxides, 3, are synthesized by alcoholysis of A with isopropanol. The reaction occurs with evolution of neopentane. Subsequent reaction with HCl in Et20 liberates... 

The Sharpless epoxidation of allylic alcohols with tert-butylhydroperoxide and titanium(IV) isoproxide has been carried out with a polymeric tartrate made from tartaric acid and 1,8-octanediol.114 The yield of epoxide (92%) was comparable with that when dimethyl tartrate was used (91%), but the 79% ee was lower than the 98% ee found with the dimethyl tartrate. It may be possible to raise the ee by further variations in the structure of the polymer. The heterogenization of a catalyst for a homogeneous reaction often requires optimization to obtain comparable or higher yields and stereospecificity. 

When the MAS experiment is appHed to quadrupolar nuclei such as Al, the quality of the NMR spectrum depends dramatically on the magnitude of compared with both the MAS spin rate and the magnetic field, Bq. Excellent spectra are obtained for small Cq sites when studied with high-speed MAS spin rates at high Bg. Conversely, Al sites can be invisible for high Cq values and modest MAS spin rates and Bo, note the evolution in line shapes for the Al MAS NMR spectra in Fig. 7.11. Likewise, the four-coordinate AIO4 sites in an aluminum isoproxide complex, with Cq = 12.3 MHz, are observable at 20 kHz and 19.6 T while three-coordinate aluminum sites in related complexes, with Cq > 30 MHz, are not observable [14],... 

Alfin polymerization n. The Alfin catalyst (Hans-Georg Elias (1977) Macromolecules, Plenum Press, New York), consists of a suspension in an inert solvent like pentane of a mixture of an alklenylsodium compound (such as allyl sodium), an alkoxide of a secondary alcohol (such as isoproxide), and an alkali halide (such as sodium chloride) the catalyst is highly specific for the polymerization of dienes into the 1,4 forms. 

V. C. Kessler, S. Cohil and S. Parola, Interaction of some divalent metal acetylacetonate with Al, Ti, Nb and Ta isoproxides. Factors influencing the formation and stability of heterometallic alkoxide complexes, Dalton Trans., vol. 4, pp. 544-550, 2003. 

The H NMR spectrum of uranium pentaisopropoxide at 13°C shows a doublet at 8 1.26, a much larger broad signal at 8 1.78 and a very broad signal, which is just detectable above the unavoidable noise, at 8 —15. These results have been interpreted in terms of the dimer/monomer behaviour of the isoproxide. At —65°C, the high-held signal splits into two equal signals and the dimeric species predominates below this temperature. ... 

The hydrolysis reaction to obtain zirconium titanate (ZT), ZrTi04, was performed with the alkoxides zirconium n-propoxide (NPZ) (Dupont), and titanium isoproxide (TFT) Dupont, deionized water in the presence of nitric acid (Merck). The solvent used was n-propanol (Merck). 

The cyclopropylamine scaffold is a recurrent moiety in several natural products or drugs [24]. However, its preparation usually requires several steps [25]. Szy-moniak and Bertus have developed an amino version of the Kulinkovich [26] reaction for quicker access to these aminocyclopropanes from nitrile derivatives, Grignard reagents, and titanium isoproxide (Scheme 9.15) [27]. Starting from p- or... 

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