Organic synthesis ethylene oxide

Poly(ethylene oxide). The synthesis and subsequent hydrolysis and condensation of alkoxysilane-terniinated macromonomers have been studied (39,40). Using Si-nmr and size-exclusion chromatography (sec) the evolution of the siUcate stmctures on the alkoxysilane-terniinated poly(ethylene oxide) (PEO) macromonomers of controlled functionahty was observed. Also, the effect of vitrification upon the network cross-link density of the developing inorganic—organic hybrid using percolation and mean-field theory was considered. 

Catalysts. Silver and silver compounds are widely used in research and industry as catalysts for oxidation, reduction, and polymerization reactions. Silver nitrate has been reported as a catalyst for the preparation of propylene oxide (qv) from propylene (qv) (58), and silver acetate has been reported as being a suitable catalyst for the production of ethylene oxide (qv) from ethylene (qv) (59). The solubiUty of silver perchlorate in organic solvents makes it a possible catalyst for polymerization reactions, such as the production of butyl acrylate polymers in dimethylformamide (60) or the polymerization of methacrylamide (61). Similarly, the solubiUty of silver tetrafiuoroborate in organic solvents has enhanced its use in the synthesis of 3-pyrrolines by the cyclization of aHenic amines (62). 

The preferred catalysts are salts of inorganic and organic acids as well as tertiary amines. Phthalic anhydride, succinic anhydride and maleic anhydride are typical acid anhydrides, while ethylene oxide, propylene oxide, epichlorohydrin and phenyl glycidyl ether are typical epoxides. The synthesis of a ladder polymer was carried out by using bisanhydrides264. ... 

A synthesis of comblike organoboron polymer/boron stabilized imidoanion hybrids was examined via reactions of poly(organoboron halides) with 1-hexylamine and oligo(ethylene oxide) monomethyl ether and subsequent neutralization with lithium hydride (scheme 8). The obtained polymers (10) were amorphous soft solids soluble in common organic solvents such as methanol, THF, and chloroform. In the nB-NMR spectra (Fig. 11), neutralization of the iminoborane unit with lithium hydride... 

Also known as glycol dinitrate. eth-o,len m,trat ethylene oxide orgchem 1. (CH2)20 A colorless gas, soluble in organic solvents and miscible in water, boiling point 11°C used in organic synthesis, for sterilizing, and for fumigating. 2. Also known as 1,2-epoxyethane epoxide oxirane eth-3,len ak,sTd ... 

Uses Solvent for cellulose acetate, ethylcellulose manufacturing insecticides, ethylene oxide, and ethylene glycol treating sweet potatoes before planting organic synthesis (introduction of the hydroxyethyl group). 

The synthesis of cyclic ethers (especially epoxides) provides important reagents for organic synthesis. Industrially, ethylene oxide is the most important ether because it is used in the synthesis of many other organic compounds. This compound forms by the cataljrtic oxidation of ethylene as seen in Figure 3-31. 

Bromine occurs in nature as bromide in many natural brine wells and salt deposits. It also is found in seawater at a concentration of 85 mg/L. The element was discovered by A. J. Balard and C. Lowig, independently in 1826. Bromine is used in bleaching fibers and as a disinfectant for water purification. Other appbcations are in organic synthesis as an oxidizing or brominat-ing agent in the manufacture of ethylene dibromide, methyl bromide and other bromo compounds for dyes and pharmaceutical uses as a fire retardant for plastics and in chemical analysis. Ethylene dibromide is used in anti-... 

Many organics also undergo oxidation of a noncombustion nature to form various commercial products. Such reactions are mostly catalytic and include production of synthesis gas, a mixture of CO and H2, conversion of ethylene to ethylene oxide, and cumene to phenol and acetone. 

The process of Shell starts from ethylene oxide, which is prepared by oxidation of ethylene. Ethylene oxide is transformed with synthesis gas in a hydro-formylation process to 3-hydroxypropanal as well, but for this reaction very high pressure (150 bar) is required [27]. The aldehyde is extracted from the organic phase with water and subjected to hydrogenation using nickel as a catalyst, again under high pressure. 

The search for a new epoxidation method that would be appropriate for organic synthesis should also, preferably, opt for a catalytic process. Industry has shown the way. It resorts to catalysis for epoxidations of olefins into key intermediates, such as ethylene oxide and propylene oxide. The former is prepared from ethylene and dioxygen with silver oxide supported on alumina as the catalyst, at 270°C (15-16). The latter is prepared from propylene and an alkyl hydroperoxide, with homogeneous catalysis by molybdenum comp e ts( 17) or better (with respect both to conversion and to selectivity) with an heterogeneous Ti(IV) catalyst (18), Mixtures of ethylene and propylene can be epoxidized too (19) by ten-butylhydroperoxide (20) (hereafter referred to as TBHP). 

Mesoporous alumina sphere was synthesized under the catalyst of hydrochloride or ammonia in organic solvents. In a typical synthesis, 1.1 g [poly(ethylene oxide)-6-poly(propylene oxide)-6-poly(ethylene oxide) triblock copolymer (Aldrich, average molecular weight 5800, EO20PO70EO20)] was dissovled in 11.0 g (0.268 mol) acetonitrile and 1.10 g (61.1 mmol) water containing 0.1 mmol HC1 or 5 mmol NH3, the solution of 3.0 g (12.2 mmol) aluminum tri-sec-butoxide dissovled in 10 g (0.24 mol) acetonitrile was slowly dropped into with stirring. After stirring for 6 h, the product was filtered and washed with acetonitrile and dried at room temperature in air. The obtained products were calcined in air at 550 °C for 4 h to remove the templates. 

Apart from the oxidation of trihexylborane,16 1-hexanol has been prepared by a previous Organic Syntheses17 procedure involving the reaction of ethylene oxide with n-butylmagnesium bromide and alternate methods of synthesis are reviewed therein. 

Devise a synthesis of each compound. You may use HC=CH, ethylene oxide, and alkyl halides as organic starting materials and any inorganic reagents. 

Additions to nonactivated olefins and dienes are important reactions in organic synthesis [1]. Although cycloadditions may be used for additions to double bonds, the most common way to achieve such reactions is to activate the olefins with an electrophilic reagent. Electrophilic activation of the olefin or diene followed by a nucleophilic attack at one of the sp carbon atoms leads to a 1,2- or 1,4-addition. More recently, transition metals have been employed for the electrophilic activation of the double bond [2]. In particular, palladium(II) salts are known to activate carbon-carbon double bonds toward nucleophilic attack [3] and this is the basis for the Wacker process for industrial oxidation of ethylene to acetaldehyde [41. In this process, the key step is the nucleophilic attack by water on a (jt-ethylene)palladium complex. 

A related synthesis utilizes ethylene oxide (Sec. 17.14) to make primary alcohols containing two more carbons than the Grignard reagent. Here, too, the organic... 

Use Organic synthesis (methanol, ethylene, isocyanates, aldehydes, acrylates, phosgene), fuels (gaseous), metallurgy (special steels, reducing oxides, nickel refining), zinc white pigments. 

Use Solvent for cellulose acetate, ethylcellulose introduction of hydroxyethyl group in organic synthesis to activate sprouting of dormant potatoes manufacture of ethylene oxide and ethylene glycol insecticides. 

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