Osmium compounds synthesis

OSO4 is obtained on oxidation of any osmium compound or by direct synthesis at 300-800°C from the elements [50], Its solubility in CCI4 and volatility make it easy to purify it forms pale yellow crystals (m.p. 40.46°C, b.p. 131°C). Like RUO4 it forms tetrahedral molecules with Os-O 1.684-1.710 A, O—Os—O 106.7-110.7° in the solid state Os-O 1.711A in the gas phase [51], It is soluble in water as well as in CCI4 and is very toxic (TLV 2.5 ppm), affecting the eyes. (Its use as a biological stain involves its reaction with tissue.)... 

The synthesis of metallopolymers containing ruthenium and/or osmium compounds by covalent attachment of the metal centers to a polymer backbone is based on the different lability of the chloride ions in the complex cis-[M(bipy)2Cl2]. Removal of the first chloride ion occurs readily by refluxing in a low boiling point alcohol, such as methanol or ethanol. Removal of the second chloride requires aqueous solvent mixtures and/or higher temperatures. Consequently for the synthesis of metallopolymers of the type [M(bipy)2(POL)nCl]Cl, heating at reflux in ethanol is sufficient, whereas for the bis-substituted materials, i.e., [M(bipy)2... 

The oxidative cleavage of C=C bond is a common type of reaction encountered in organic synthesis and has played a historical role in the structural elucidation of organic compounds. There are two main conventional methods to oxidatively cleave a C=C bond (1) via ozonol-ysis and (2) via oxidation with high-valent transition-metal oxidizing reagents. A more recent method developed is via the osmium oxide catalyzed periodate oxidative cleavage of alkenes. All these methods can occur under aqueous conditions. 

Aspects of the apparatus for the synthesis using metal atoms are described. The reactions of the atoms of rhenium, tungsten, and osmium with hydrocarbons including alkanes are described. It is shown that metal atom reactions with alkanes can give isolable organometallic compounds including l-alkylidene compounds. 

Chloroxytrifluoromethane, 26 137-139 reactions, 26 140-143 addition to alkenes, 26 145-146 oxidative addition, 26 141-145 vibrational spectra, 26 139 Chloryl cation, 18 356-359 internal force constants of, 18 359 molecular structure of, 18 358, 359 properties of, 18 357, 358 synthesis of, 18 357, 358 vibrational spectra of, 18 358, 359 Chloryl compounds, reactions of, 5 61 Chloryl fluoride, 18 347-356 chemical properties of, 18 353-356 fluoride complexes of, 5 59 molecular structure of, 18 349-352 physical properties of, 18 352, 353 preparation, 5 55-57 and reactions, 27 176 properties of, 5 48 reactions, 5 58-61, 18 356 synthesis of, 18 347-349 thermal decomposition of, 18 354, 355 vapor pressures, 5 57, 18 353 vibrational spectra of, 18 349-352 Chloryl ion, 9 277 Cholegobin, 46 529 Cholesterol, astatination, 31 7 Cholorofluorphosphine, 13 378-380 h CHjPRj complexes, osmium, 37 274 Chromatium, HiPIP sequence, 38 249 Chromatium vinosum HiPIP, 38 108, 133 Fe4S4 + core, 33 60 Chromato complexes, osmium, 37 287... 

A base-catalyzed, elimination reaction was a key step in a synthesis of D-ribose from L-glutamic acid.188 In that work, L-glutamic acid was converted, by a series of reactions, into 5-0-benzyl-2,3-dideoxy-D-glycero-pentofuranose (157) from compound 157, a mixture of glycosides was obtained which, on treatment with bromine and calcium carbonate, gave the monobromo derivative 158 as a mixture of diastereoisomers. Base-catalyzed dehydrobromination of 158 afforded the unsaturated derivative 159. Hydroxylation of 159 with potassium permanganate or with osmium tetraoxide gave a mixture of methyl 5-0-benzyl-/3-D-ribofuranoside and methyl 5-O-benzyl-a-D-lyxofuranoside. 

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