Ferric chloride epoxides

Ferric chloride/epoxide FeCl3/propylene oxide (7)... 

A mixture of epoxides 483 obtained on oxidation of 482 with dimethyldioxirane, when exposed to ferric chloride provided, as the kinetically controlled product, the a-aldehyde 484, which without purification was reduced to the a-alcohol 485. The exclusive formation of 484 is believed to occur via the benzyl cation 486, generated by Lewis-acid opening of the oxirane ring, suffering a stereospecific kinetic 1,2-hydride shift The amino alcohol 487 obtained after sequential removal of O-benzyl and N-tosyl groups from 485, on treatment with triphenylphosphine and iodine in the presence of imidazole furnished the tetracyclic base 488, which was oxidised to the ketone 489. Trapping of the kinetically generated enolate of 489 as the silylether, followed by palladium diacetate oxidation yielded the enone 490. The derived... 

The first report on the coordination polymerisation of epoxide, leading to a stereoregular (isotactic) polymer, concerned the polymerisation of propylene oxide in the presence of a ferric chloride-propylene oxide catalyst the respective patent appeared in 1955 [13]. In this catalyst, which is referred to as the Pruitt Baggett adduct of the general formula Cl(C3H60)vFe(Cl)(0C3H6),CI, two substituents of the alcoholate type formed by the addition of propylene oxide to Fe Cl bonds and one chlorine atom at the iron atom are present [14]. A few years later, various types of catalyst effective for stereoselective polymerisation of propylene oxide were found and developed aluminium isopropoxide-zinc chloride [15], dialkylzinc-water [16], dialkylzinc alcohol [16], trialkylalumi-nium water [17] and trialkylaluminium-water acetylacetone [18] and trialkyla-luminium lanthanide triacetylacetonate H20 [19]. Other important catalysts for the stereoselective polymerisation of propylene oxide, such as bimetallic /1-oxoalkoxides of the [(R0)2A10]2Zn type, were obtained by condensation of zinc acetate with aluminium isopropoxide in a 1 2 molar ratio of reactants [20-22]. 

H. Sugimoto, D. T. Sawyer, Ferric chloride induced activation of hydrogen peroxide for the epoxidation of alkenes and monoxygenation of organic substrates in acetonitrile, J. Org. Chem. 50 (1985) 1784. 

TRICHLOROBIS (4-CHLORO-PHENYL)ETHANE or 1,1,1-TRICHLORO-2,2-BIS (p-CHLORO-PHENYL)ETHANE (50-29-3) C,4H,Cls Combustible solid (flash point 324 to 340°F/162 to 171°C). Incompatible with strong oxidizers reducing agents, including metal hydrides, nitrides, sulfides, alkali metals, and metal alkyls ferric chloride aluminum chloride salts of iron or aluminum alkalis and alkaline media. May be incompatible with many alkali metals amines, azo conqjounds diazo compounds epoxides such as glycidol, nitrides. Reacts with almninum and iron. On small fires, use water, foam, dry chemical or CO2 extinguishers. 

Deoxygenation of epoxides. n-ButyUithium (2-3 eq.) reacts with ferric chloride in THF at -78° to form a black, soluble iron species that converts epoxides into olefins in about 60-90% yield. The reaction is not stereospecific for example, the oxide of c -stilbene is converted into cu-stilbene and trans-stilbene in the ratio 89 11. ... 

DEOXYGENATION, EPOXIDES Ferric chloride-n-Butyllithium. Potassium seleno-cyanate. Sodium cyclopentadienyldicarbonylferrate. Tungsten hexachloride. 

EPOXIDES Alumina. Aluminum iso-propoxide. f-Butyl dilithioacetoacetate. Diethylaluminum 2,2,6,6-tetramethyl-piperidide. Dilithioacetate. Dimethyl malonate. Ferric chloride-Silica gel. Lithium acetylide. Lithium di-isopropylamide. Sodium boro-hydride. 

Propylene oxide has an asymmetric carbon atom. The normal commercial epoxide is a racemic mixture of the d- and 1-isomers. Osgan and Price did extensive work with both the 1-propylene oxide and the d,l-propylene oxide in both potassium hydroxide and ferric chloride/propylene oxide-initiated polymerizations. Their results are summarized in Table 5 (48). C. C. Price and coworkers first demonstrated that polymerization of pure 1-propylene oxide with an anhydrous potassium hydroxide (solid KOH) initiator led to a crystalline, rather than the usual amorphous, liquid, polymer. After extensive study by a number of researchers (69), this polymerization was shown to proceed by a stepwise anionic mechanism. The uses found for polymers of propylene oxide largely have been those requiring the amorphous polymer in elastomeric applications. Stereospecificity, however, has proved to be a key tool in understanding the polymerization mechanisms. 

More recently Tabushi et have used oxygenated Fe (TpivPP)Cl in the presence of HCl and H2-colloidal platinum supported on poly(vinylpyrrolidone) in the presence of acid chlorides as a cytochrome P450 mimic. Under such conditions cyclohexene is converted to its epoxide and slow reduction of the ferric complex followed by formation of the dioxygen ferrous complex completes the catalytic cycle. 

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