Osmium VIII oxide

Other examples are the use of osmium(VIII) oxide (osmium tetroxide) as catalyst in the titration of solutions of arsenic(III) oxide with cerium(IV) sulphate solution, and the use of molybdate(VI) ions to catalyse the formation of iodine by the reaction of iodide ions with hydrogen peroxide. Certain reactions of various organic compounds are catalysed by several naturally occurring proteins known as enzymes. 

In a similar reaction, 2,3,6-trimethoxydibenz[6,/]oxepin gives 10,11-dihydro-2,3,6-trimeth-oxydibenz[/>,/]oxepin-cw-10,l 1-diol upon treatment with osmium(VIII) oxide in the presence of A-methylmorpholine A -oxide.262 When treated with acid the diol undergoes a pinacol rearrangement to the corresponding xanthene-9-carbaldehyde. 

Chlorins, e.g. 14, form adducts with osmium(VIII) oxide, which can be hydrolyzed in aqueous sodium sulfide to bacteriochlorindiols, e g. 2, or isobacteriochlorindiols, e.g. 3. Thus, similar to diimide reductions of chlorins, metal-free tetraphenylchlorin 14 (M = 2H) is selectively oxidized to a corresponding bacteriochlorin 2 whereas the zinc chlorin gives an isobac-teriochlorin 3 on oxidation with osmium(VIII) oxide.40 With less symmetrical chlorins, very complex mixtures of constitutional isomers and stereoisomers are formed by /i-bishydroxyla-tion.17... 

Oxidation of porphyrins and chlorins with osmium(VIII) oxide is an equally valuable method to produce bacteriochlorins, although it also leads to problems of regio- and stereoselectivity. 

In the case of the osmium(VIII) oxide oxidation of 5,10,15,20-tetraphenylchlorin,3b the metal-free macrocycle gives the bacteriochlorin 6, whereas the corresponding zinc derivative leads to an isobacteriochlorin. 

If a mixture of diphenyl sulphide and the corresponding sulphoxide are treated with osmium tetroxide in boiling ether for 48 hours the sulphide is unchanged whilst the sulphoxide is converted into the sulphone in 96% yield with concomitant production of osmium trioxide . It thus seems that this method would be useful synthetically for the preparation of sulphones from sulphoxides containing sulphide functionalities. Ruthenium tetroxide may be used in place of osmium(VIII) oxide . 

Manganese trichloride oxide, 4141 Mercury(I) oxide , 4613 Mercury(II) oxide, 4605 Molybdenum(IV) oxide, 4716 Molybdenum(VI) oxide, 4717 Nickel(II) oxide, 4821 Nickel(III) oxide, 4823 Nickel(IV) oxide, 4822 Niobium(V) oxide, 4818 Osmium(IV) oxide, 4833 Osmium(VIII) oxide, 4858 Palladium(II) oxide, 4825 Palladium(III) oxide, 4848 Palladium(IV) oxide, 4835... 

Nitrosyl tetrafluorochlorate, 3985 Nitrous acid, 4435 Nitryl chloride, 4025 Nitryl fluoride, 4303 Nitryl hypochlorite, 4026 Nitryl hypofluorite, 4304 Nitryl perchlorate, 4029 Osmium hexafluoride, 4370 Osmium(VIII) oxide, 4858 Oxygen (Gas), 4831 Oxygen (Liquid), 4832 Oxygen difluoride, 4317 Ozone, 4846... 

Formula OSO4 MW 254.23 Synonym osmium(VIII) oxide. 

A mixture of a catalytic amount of osmium(VIII) oxide and excess of TV-methylmorpholine /V-oxide (NMO) dihydroxylated 1-(6-chloro-9//-purin-9-yl)-3-methylenecyclobutane and l-(2-amino-6-chloro-9i/-purin-9-yl)-3-methylenecyclobutane to give 1 and 2, respectively.44... 

Alternatively, the cyclobutanones can be made by two-step procedures, i.e. osmium(VIII) oxide oxidation to the diol followed by further oxidation either by lead(IV) acetate 85 or sodium periodate,86,87 or epoxidation followed by oxidation with periodic acid,15,63 are reported to yield the ketones. 

Nitrogen dioxide, 4720 Nitrogen oxide, 4719 Nitrosyl chloride, 4017 Nitrosyl fluoride, 4296 Nitrosyl perchlorate, 4021 Nitrosyl tetrafluorochlorate, 3979 Nitrosylsulfuric acid, 4432 Nitrous acid, 4429 Nitryl chloride, 4019 Nitryl fluoride, 4297 Nitryl hypochlorite, 4020 Nitryl hypofluorite, 4298 Nitryl perchlorate, 4023 Osmium hexafluoride, 4364 Osmium(VIII) oxide, 4852 Oxygen difluoride, 4311 Oxygen (Gas), 4825 Oxygen (Liquid), 4826 Ozone, 4840... 

Orthotelluric acid, 3 145,147 Osmium compounds, nitrido, 6 204 Osmium (IV) oxide, formation of black, by ammonium hexa-bromoosmate(IV), 5 206 Osmium(VIII) oxide, precautions in using, 5 205... 

SYNS OSMIC ACID OSMIUM(VIII) OXIDE RCRA WASTE NUMBER P087... 

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