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Cesium sulfate reaction with

Cesium fluoroxysulfate, CsSO.,f (1). Mol. wt. 247.97, stable solid at - I O, stable in CHyCN for about a day. The reagent is prepared by reaction of cesium sulfate in water with fluorine.1... [Pg.84]

Xenon difluoride is a better fluorinaling reagent for vinyltin compounds than cesium fluoroxysulfate (compare entry 1 in Tables 1 and 2). Besides this, cesium fluoroxysulfate (which can be prepared from elemental fluorine and cesium sulfate) is known to be shock sensitive and to undergo detonation upon hcaling. However, cesium fluoroxysulfate is the alternative choiee in the ease of some vinyltin compounds, such as 2- and 3-(trimethylstannyl)indolcs (Table 2, entries 5 7), whose reactions with xenon difluoride are not effective. [Pg.297]

Lead(II) nitrate reacts with cesium sulfate in an aqueous precipitation reaction. What are the formulas of lead(II) nitrate and cesium sulfate Write the molecular equation and net ionic equation for the reaction. What are the names of the products Give the molecular equation for another reaction that produces the same precipitate. [Pg.172]

Addmon of cesium fluoroKysuIfate to olefins gives vicinal fluoroalky I sulfates with low regio- and stereoselectivity [162, 16J] (equations 12 and 13) Reactions of this reagent with olefins in methanol or acetic acid give vicinalfluoroalkyl methy I ethers or acetates, respectively [164, 165 166] (equation 14), with a predominance... [Pg.72]

The white cesium fluoroxy sulfate precipitates from the reaction medium and may be kept for several months in the cold (0 to -15 °C) Metal surfaces can cause detonation of the reagent. The reaction scope of cesium fluoroxysulfate seems narrower than that of acetyl hypofluorite because of its limited solubility in organic solvents Cesium fluoroxysulfate has not been prepared with a fluorine-18 label. [Pg.134]

The reaction of elemental tellurium with cesium 3-cow io-3-cobaltabis[decahydro-l,2-dicarba-c/o.vo-dodecaborate] in acetic anhydride/sulfuric acid and the methylation of the resulting product with dimethyl sulfate produced 8,8 -methylielluro-3-commo-3-cobaltabis[l,2-dicarba-closo-dodecaborane in low yield3. [Pg.184]

Cesium-exchanged zeolite X was used as a solid base catalyst in the Knoevenagel condensation of benzaldehyde or benzyl acetone with ethyl cyanoacetate [121]. The latter reaction is a key step in the synthesis of the fragrance molecule, citronitrile (see Fig. 2.37). However, reactivities were substantially lower than those observed with the more strongly basic hydrotalcite (see earlier). Similarly, Na-Y and Na-Beta catalyzed a variety of Michael additions [122] and K-Y and Cs-X were effective catalysts for the methylation of aniline and phenylaceto-nitrile with dimethyl carbonate or methanol, respectively (Fig. 2.37) [123]. These procedures constitute interesting green alternatives to classical alkylations using methyl halides or dimethyl sulfate in the presence of stoichiometric quantities of conventional bases such as caustic soda. [Pg.81]

Methyl terf-butyl ether (MTBE) is an important industrial product used as oxygenate additive in reformulated gasoline. Environmental concern makes its future uncertain, however. Although mainly manufactured by reaction of isobutylene with methanol, it is also produced commercially from methanol and fcrr-butyl alcohol, a by-product of propylene oxide manufacture. Numerous observations from the use of heteropoly acids have been reported. These compounds were used either as neat acids [74], or supported on oxides [75], silica or K-10 montmorillonite [76]. They were also used in silica-included form [77] and as acidic cesium salts [74,77]. Other catalysts studied were sulfated ZrOj [76], Amberlyst 15 ion-exchange resin [76], HZSM-5 [76], HF-treated montmorillonite, and commercial mineral acid-activated clays [75]. Hydrogen fluoride-treatment of montmorillonite has been shown to furnish particularly active and stable acid sites thereby ensuring high MTBE selectivity (up to 94% at 413 K) [75]. [Pg.300]

The selective oxidation of ethylene to ethylene oxide (EO) is performed on supported silver catalysts at temperatures of250—280 °C, and a pressure of roughly 20 bar. In this process, it is necessary to avoid secondary reactions of EO. Typical industrial catalysts may contain 8—15 wt% silver dispersed on low surface area (X-AI2O3 (0.5-1.3 m g ) with a porosity of about 0.2—0.7 cm g In addition, the catalyst may contain several promoters in varying amounts (ppm by weight) 500—1200 ppm alkali metal (mostly cesium), 5-300 ppm of sulfur as cesium or ammonium sulfate, 10-300 ppm offluorine as ammonium fluoride, or alkaft metal fluoride (427). [Pg.389]

Typical procedure. O-A-PhenylbutYl-O -butyl carbonate 989 [711] To 4-phenyl-l-buta-nol 985 (100 mg, 0.67 mmol) in anhydrous DMF (1.6 mL, 0.4 m) were added cesium carbonate (625 mg, 2.10 mmol, 3 equiv.) and tetrabutylammonium iodide (208 mg, 0.67 mmol, 1 equiv.). CO2 gas (flow rate 25-30 mL min ) was bubbled into the reaction mixture for 2-3 min, and then 1-bromobutane 988 (274 mg, 0.22 mL, 2.0 mmol) was added to the suspension. The reaction proceeded at ambient temperature with CO2 gas bubbling for 3.5 h, after which time the starting material (4-phenyl-l-butanol) had been consumed. The reaction mixture was then poured into water (30 mL) and extracted with hexanes/EtOAc (3 1 v/v, 60 mL). The organic layer was washed with water (2 x 30 mL) and brine (30 mL), and dried over anhydrous sodium sulfate. Evaporation of the solvent followed by flash column chromatography (hexanes/EtOAc, 9 1 v/v) afforded 0-4-phenylbutyl-0 -butyl carbonate 989 (157 mg, 94%) as a colorless oil. [Pg.258]

The reaction of 2-amino-3-(2-propyityl)tliiazolium bromide with various iodo-benzenes, catalyzed by Pd/Cu, in the presence of sodium lauiyl sulfate as surfactant and cesium carbonate as base, in water, leads to the formation of 6-substituted imidazo[2,l-b]thiazoles [19]. [Pg.243]


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