Al isopropoxide

The surface of Li(Ni0.4Co0.2Mn0.4)O2 was coated with amorphous aluminum oxide using Al-isopropoxide. The as-prepared and coated materials exhibited almost no differences in initial capacity and impedance. However, during the extended cycling, the uncoated material exhibited significant capacity fading. 

Ti-Mordenite has been obtained by reaction of TiCI4 with dealuminated mordenite and by hydrothermal synthesis. The reaction of TiCl4 with dealuminated mordenite was carried out at 723 K following the method of Kraushaar and van Hooff (1988, 1989). In the hydrothermal synthesis, Si02 powder, NaOH, Al isopropoxide, and TBOT react at 448 K for 3 days (Kim et al., 1993). 

Grafting of Al on SBA-15 was performed from Al isopropoxide, Al(0-iPr)3 (Aldrich). This compound was dissolved in 20 mL of either anhydrous isopropanol (Fluka) or anhydrous cyclohexane (Fluka) before suspending the SBA-15 support previously dehydrated for 2h at 450°C. In order to avoid the presence of any traces of water the reaction was performed in Ar atmosphere. The suspension was left under stirring overnight before filtration and washing with the corresponding anhydrous solvent. The solid was then calcined at 500°C for 4h. This material corresponds to the grafting. The whole procedure was... 

Al isopropoxide, MCM-41 secondary treatment Alkane diffusion, silicalite-l 19-P-lO... 

FlO. 5. Comparison of the desorption chromatograms of ethylene smd butene on alumina (from Al-isopropoxide) without evacuation before desorption. Preadsorption at room temperature. The amounts of olefins preadsorbed and the adsorption pressures C2H4 0.261 cc/gm, 10 2 mm C4Hg 0.257 cc/gm, 10 mm. 

Al-isopropoxide, Al-tert-butoxide, Al-phenoxide, Al-cyclo-hexoxide Al-anilide (CHgCOO)gTl Al-silicate Anhydrous silicate Clay, Kaolin, Super-filtrol, Montmorillo-nite. Zeolite Pumice... 

N-Bromosuccinimide added at -50° to a stirred soln. of dehydro-retro-carotene in chloroform-acetic acid, stirred 7 min., N,N-diethyIaniline added, stirring continued 2 hrs. at 0°, the crude product stirred 2 hrs. at 40° with benzene and methanolic 10%-KOH, the resulting crude isozeaxanthin dissolved in benzene, Al-isopropoxide and acetone added, stirred and refluxed 16 hrs. under Ng -> canthaxanthin. Y 74%. F. e. s. J. D. Surmatis et al., Helv. 55, 974 (1970). 

Before considering the mechanism of this important variant of asymmetric hydrogen transfer, let us first look at earlier methods used in the field. Most of them were based on 2-propanol as the favourable organic source of hydrogen, and represent catalytic variants of the Meerwein-Verley-Ponndorf name reaction which uses large quantities of Al-isopropoxide at elevated temperatures (Scheme 11.7) [27, 28]. 

CuHal, CuCl, CuBr, Cul, (CHgC00)2Cd Al-isopropoxide, Al-tert-... 

Al-isopropoxide followed by a soln. of excess diazomethane in methylene chloride added to a soln. of yohimbine in the same solvent, and the product isolated after 12 hrs. yohimbine methyl ether. Y 84%. F. e. s. A. Popelak and G. Lettenbauer, Arch. Pharm. 295, 427 (1962). 

A warm soln. of Al-isopropoxide in abs. isopropanol added dropwise during 10-15 min. at 50° to a soln. of methyl 4-methyl-5,8-dioxo-cis-1,4,5,8,9,10-hexa-hydronaphthalenecarboxylate in abs. isopropanol, after 1 hr. at 50° isopropanol distilled off in vacuo at 50° in a Ng-atmosphere with increasing rate of distillation so that most of the isopropanol is removed after 1.5 hrs., cooled to 30-40°, treated with dil. H2SO4, then the remaining isopropanol distilled off in vacuo... 

Ketene passed at room temp, in a Ng-stream into a mixture of acetophenone, titanium isopropoxide, and ether (or pentane), ice-cooled, and treated with 10%-sulfuric acid isopropyl / -hydroxy-/ -phenylbutyrate. Y 88%. F. e. s. L. Vuitel and A. Jacot-Guillarmod, Synthesis 1972, 608 Helv. 57, 1703 (1974) with Al-isopropoxide s. K. Inomata, T. Kawahara, and T. Mukaiyama, Chem. Lett. 1974, 245. 

Modified Meerwein-Ponndorf-Verley reaction. 4,4 - Bisphenethynyldesoxy-benzoin heated with Al-isopropoxide for 1.5 hrs. at 170-180, then for 0.5 hr. 

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