Organic epoxidation

Aryl ether dendrimer 1,627 = [GO] 0.61" [GO] Common organic Epoxidation and cyclo- Precipitation, [129]... 

Gash AE, Satcher JH, Simpstm RL (2004) Monolithic nickel(II)-based aerogels using an organic epoxide The importance of the counterion. J Non-Cryst Solids 350 145-151. 

The organic epoxide reagent (ethylene oxide, propylene oxide, and epichloro-hydrin) serves as proton scavenger and is stoichiometrically consumed in this sol-gel reaction. Given the higher acidity of water ligands of solvated metal cations (salts) in solution, they tend to spontaneously form hydroxide ligands (see Eq. (17.5)). The proton that is released can protonate the epoxide ... 

Bromine is used in the manufacture of many important organic compounds including 1,2-dibromoethane (ethylene dibromide), added to petrol to prevent lead deposition which occurs by decomposition of the anti-knock —lead tetraethyl bromomethane (methyl bromide), a fumigating agent, and several compounds used to reduce flammability of polyester plastics and epoxide resins. Silver(I) bromide is used extensively in the photographic industry... 

Alkylation of Enolates (condensation of enolates with alkyl halides and epoxides) Comprehensive Organic Synthesis 1991, vol. 3, 1. 

To a mixture of 100 ml of THF and 0.10 mol of the epoxide (note 1) was added 0.5 g Of copper(I) bromide. A solution of phenylmagnesium bromide (prepared from 0.18 mol of bromobenzene, see Chapter II, Exp. 5) in 130 ml of THF was added drop-wise in 20 min at 20-30°C. After an additional 30 min the black reaction mixture was hydrolysed with a solution of 2 g of NaCN or KCN and 20 g of ammonium chloride in 150 ml of water. The aqueous layer was extracted three times with diethyl ether. The combined organic solutions were washed with water and dried over magnesium sulfate. The residue obtained after concentration of the solution in a water-pump vacuum was distilled through a short column, giving the allenic alcohol, b.p. 100°C/0.2 mmHg, n. 1.5705, in 75% yield. 

Functional group transformations of epoxides rank among the fundamental reactions of organic chemistry and epoxides are commonplace natural products The female gypsy moth for example attracts the male by emittmg an epoxide known as disparlure On detechng the presence of this pheromone the male follows the scent to its ongm and mates with the female... 

Carey Organic Chemistry I 16 Ethers Epoxides and I Text Fifth Edition Sulfides... 

In general, the peilluoioepoxides have boiling points that are quite similar to those of the corresponding fluoroalkenes. They can be distinguished easily from the olefins by it spectroscopy, specifically by the lack of olefinic absorption and the presence of a characteristic band between 1440 and 1550 cm . The nmr spectra of most of the epoxides have been recorded. Litde physical property data concerning these compounds have been pubhshed (Table 1). The stmcture of HFPO by electron diffraction (13) as well as its solubility and heats of solution in some organic solvents have been measured (14,15). 

The direct oxidation of fluoroalkenes is also an excellent general synthesis procedure for the preparation of perfluoroepoxides (eq. 8). This method exploits the low reactivity of the epoxide products to both organic and inorganic free radicals. 

Many PVC stabilizer formulations also contain one or more organic costabilizers that can also absorb hydrogen chloride. Typical of these additives are epoxidized fatty acid esters and organophosphites ... 

Displacement of activated chlorine atoms also proceeds with certain types of organic compounds, but only in the presence of Lewis acid catalysts. Particular examples include epoxides, polyhydric alcohols, trialkylphosphites (12), and P-aminocrotonates (13). These additives are commonly used in conjunction with metallic stabilizers to provide complete, high performance, commercial stabilizer packages. 

In general, peroxomonosulfates have fewer uses in organic chemistry than peroxodisulfates. However, the triple salt is used for oxidizing ketones (qv) to dioxiranes (7) (71,72), which in turn are useful oxidants in organic chemistry. Acetone in water is oxidized by triple salt to dimethyldioxirane, which in turn oxidizes alkenes to epoxides, polycycHc aromatic hydrocarbons to oxides and diones, amines to nitro compounds, sulfides to sulfoxides, phosphines to phosphine oxides, and alkanes to alcohols or carbonyl compounds. 

Obsolete uses of urea peroxohydrate, as a convenient source of aqueous hydrogen peroxide, include the chemical deburring of metals, as a topical disinfectant and mouth wash, and as a hairdresser s bleach. In the 1990s the compound has been studied as a laboratory oxidant in organic chemistry (99,100). It effects epoxidation, the Baeyer-Villiger reaction, oxidation of aromatic amines to nitro compounds, and the conversion of sodium and nitrogen compounds to S—O and N—O compounds. 

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