Precursors isopropanol

The main use of acrolein is to produce acrylic acid and its esters. Acrolein is also an intermediate in the synthesis of pharmaceuticals and herhicides. It may also he used to produce glycerol hy reaction with isopropanol (discussed later in this chapter). 2-Hexanedial, which could he a precursor for adipic acid and hexamethylene-diamine, may he prepared from acrolein Tail to tail dimenization of acrolein using ruthenium catalyst produces trans-2-hexanedial. The trimer, trans-6-hydroxy-5-formyl-2,7-octadienal is coproduced. Acrolein, may also he a precursor for 1,3-propanediol. Hydrolysis of acrolein produces 3-hydroxypropionalde-hyde which could he hydrogenated to 1,3-propanediol. ... 

Van der Schaaf et al. described a synthesis of the 14-electron complex [RuHCl(PPr13)2] (32) from [RuCl2(COD)]A.,PPr31,isopropanol,and abase.Compound 32 is a suitable precursor for ruthenium carbene complex 33, as outlined in Scheme 10. Although 32 was isolated and structurally characterized, it may also be generated in situ for the preparation of the carbene complex 33 [18]. 

PfefFer, de Vries and coworkers developed the use of ruthenacycles, based on chiral aromatic amines as enantioselective transfer hydrogenation catalysts. These authors were able to develop an automated protocol to produce these catalysts by reacting ligand and metal precursor in the presence of base, KPFS in CH3CN. After removal of the solvent, isopropanol was added followed by the substrate, acetophenone, and KOtBu. In this way, a library of eight chiral... 

Post-synthesis alumination using A1(N03)3 as the precursor improves the acidity of siliceous MCM-41 materials significantly. FTIR results show that both Bronsted and Lewis acid sites are increased upon alumination. The number of acid sites increases with the Al content on MCM-41. NH3-TPD reveals the mild strength of these created acid sites. Due to the improved acidity, the catalytic activity for dehydration of isopropanol to propylene over these alumina-modified MCM-41 materials is considerably promoted by post-synthesis alumination. The results of XRD and N2 adsorption show that the enhancement of acidity for siliceous MCM-41 by postsynthesis alumination does not cause any serious structural deformation of the resulting material. 

It has been demonstrated that skeletal nickel catalysts can be modified with tin by using CSRs taking place between tin alkyls and hydrogen adsorbed on nickel. Upon applying this type of modification the selectivity pattern of the catalysts in the reductive ami-nation of acetone can be tailored. Selective poisoning of sites responsible for the formation of isopropanol could be achieved by using tin dibenzyl (or diethyl] dichloride as tin precursor compound. ... 

Coteiro s group studied the influence of the solvent to the ternary oxide, Ru-Ti-Sn, electrode stability (Coteiro et al. 2006). The precursor mixtures were prepared by dissolving RuCh H20, TiCl4, and SnCl2 2H20 salts into the solvent. Two different solvents, HC1/H20 (1 1 v/v) or isopropanol, were applied. The results with isopropanol as solvent showed that tin loss can be eliminated and higher elec-trochemically active area and stability can be achieved, when compared with HC1 solution. 

Furthermore, much work has been devoted to the development of stereoselective methods for preparing terminally functionalized 3,5-dihydroxy carboxylates. Muller et al. developed a new chemoenzymatic synthesis of the chlorinated 5-hydroxy-3-keto ester as the precursor for the dihydroxy hexanoate [169, 170]. The diketo ester is reduced exclusively in the C5 position by NADP+-dependent ADH from L. kefir or L. brevis. NADPH is regenerated by an excess of isopropanol by the same enzyme [171, 172] (Fig. 43). High concentrations of isopropanol are... 

Hutchings and coworkers (78-83) pioneered the use of supercritical antisolvent precipitation to prepare a number of catalyst and support materials including vanadium phosphates. Vanadium phosphate precursor solutions were prepared from VOCI3 and H3PO4 refluxed in isopropanol. In the supercritical antisolvent precipitation method, a solution of the material to be precipitated and supercritical CO2 are pumped through a coaxial nozzle at temperatures and pressures above the critical point of... 

Figure 1 shows cross-section TEM images of a MOVPE-grown ZnO layer on Al203(0001) with a 40 nm GaN buffer layer deposited prior to the ZnO growth. Isopropanol and Diethylzinc were used as precursors for the ZnO deposition with a Vl/II-flux ratio of 36 at total reactor pressure of 400 mbar and hydrogen as a carrier gas. The substrate temperature was 380 °C. 

Hydrosilylation is by far the most important ronte for obtaining monomers and other precursors to fluorinated polysiloxanes. Hydrosylilation [104] is the addition of silicon hydride moiety across an unsatnrated linkage nsing transition metal complexes of platinum or rhodium such as Speier s catalyst, hexachloroplatinic acid in isopropanol [103], The preparation of methyl(3,3,3-triflnoropropyl)dichlorosilane, which is the precnrsor of the indnstrially most important PMTFPS, is described in patent literatnre [105],... 

In 1999, Brasseur-Tilmant [56] presented a work dealing with modification of macroporous alumina media by TiOi particles deposition using supercritical isopropanol. The aim was to prepare inorganic membranes for cross-fiow filtration. Anatase particles were deposited on plane alumina support after thermal decomposition of titanium alkoxide precursors. A slight infiltrated zone was observed and a pore size reduction was achieved from 110 to 5 nm, leading to obtain fine ultrafiltration membranes. The main problem was to control the reaction at the membrane interface and not in the porosity, and moreover, this process was suitable for mbular membrane preparation. 

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