Osmium tetroxide with hydrogen peroxide

Hydroxylation at double bonds of unsaturated carboxylic acids is accomplished stereoselectively by the same reagents as those used to hy-droxylate alkenes. syn Hydroxylation is carried out with potassium permanganate [101] or osmium tetroxide with hydrogen peroxide [130], sodium chlorate [310, 715], potassium chlorate [715], or silver chlorate [310] as reoxidant, anti Hydroxylation is achieved with peroxyacids, such as peroxybenzoic acid [310] or peroxyformic acid, prepared in situ from hydrogen peroxide and formic acid [101] (equation 472). 

Hydroxylation of the double bond of methyltestosterone by means of osmium tetroxide and hydrogen peroxide affords the 4,5 diol. This undergoes beta elimination on treatment with base to yield oxymestrone (83). ... 

Then, pseudo-p-DL-gulopyranose (14) was synthesized by hydroxylation of 2,5-di-hydroxy-3-cyclohexene-l-methanol triacetate (12), which was prepared by Diels-Alder cycloaddition of 1,4-diacetoxy- 1,3-butadiene (10) and allyl acetate (11), with osmium tetroxide and hydrogen peroxide and successive acetylation as the pentaacetate (13). Analogous hydrolysis of 13 in ethanolic hydrochloric acid afforded the free pseudosugar 14 in 33% yield from 12 [2] (Scheme 7). 

Two pseudo-sugars of P-L-allo and a-D-manno have been prepared from the preceding intermediate 143 as follows. Reduction of 143 with diisobutyl aluminium hydride afforded the 3-hydroxyl derivative (155), which gave the 3-O-acetyl derivative (156) on acetylation. Hydroxylation of 156 with osmium tetroxide and hydrogen peroxide gave the compound (157), m.p. 154-155 °C, [a] 1 +71.5° (chloroform), as a main component (53% yield) and an unidentified compound, m.p. 191-193 °C, [a.] —7.9° (chloroform), as a minor component (6% yield). On acetylation, 157 was converted into the tri-0-acetyl derivative (158), m.p. 66-67 °C, [a]23 +41.8° (chloroform). 

Oxidation. Maleic and fumaric acids are oxidized in aqueous solution by ozone [10028-15-6] (qv) (85). Products of the reaction include glyoxyhc acid [298-12-4], oxalic acid [144-62-7], and formic acid [64-18-6], Catalytic oxidation of aqueous maleic acid occurs with hydrogen peroxide [7722-84-1] in the presence of sodium tungstate(VI) [13472-45-2] (86) and sodium molybdate(VI) [7631-95-0] (87). Both catalyst systems avoid formation of tartaric acid [133-37-9] and produce i j -epoxysuccinic acid [16533-72-5] at pH values above 5. The reaction of maleic anhydride and hydrogen peroxide in an inert solvent (methylene chloride [75-09-2]) gives permaleic acid [4565-24-6], HOOC—CH=CH—CO H (88) which is useful in Baeyer-ViUiger reactions. Both maleate and fumarate [142-42-7] are hydroxylated to tartaric acid using an osmium tetroxide [20816-12-0]/io 2LX.e [15454-31 -6] catalyst system (89). 

Because osmium tetroxide is expensive, and its vapors are toxic, alternate methods have been explored for effecting vic-glycol formation. In the aliphatic series, olefins can be hydroxylated with hydrogen peroxide with the use of only a catalytic amount of osmium tetroxide. Anhydrous conditions are not necessary 30% hydrogen peroxide in acetone or acetone-ether is satisfactory. The intermediate osmate ester is presumably cleaved by peroxide to the glycol with regeneration of osmium tetroxide. When this reaction was tried on a A -steroid, the product isolated was the 20-ketone ... 

Similar hydroxylation-oxidations can be carried out using a catalytic amount of osmium tetroxide with A-methylmorpholine oxide-hydrogen peroxide or phenyliodosoacetate." A recent patent describes the use of triethylamine oxide peroxide and osmium tetroxide for the same sequence. Since these reactions are of great importance for the preparation of the di-hydroxyacetone side-chain of corticoids, they will be discussed in a later section. 

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. 

The preparation of Pans-1,2-cyclohexanediol by oxidation of cyclohexene with peroxyformic acid and subsequent hydrolysis of the diol monoformate has been described, and other methods for the preparation of both cis- and trans-l,2-cyclohexanediols were cited. Subsequently the trans diol has been prepared by oxidation of cyclohexene with various peroxy acids, with hydrogen peroxide and selenium dioxide, and with iodine and silver acetate by the Prevost reaction. Alternative methods for preparing the trans isomer are hydroboration of various enol derivatives of cyclohexanone and reduction of Pans-2-cyclohexen-l-ol epoxide with lithium aluminum hydride. cis-1,2-Cyclohexanediol has been prepared by cis hydroxylation of cyclohexene with various reagents or catalysts derived from osmium tetroxide, by solvolysis of Pans-2-halocyclohexanol esters in a manner similar to the Woodward-Prevost reaction, by reduction of cis-2-cyclohexen-l-ol epoxide with lithium aluminum hydride, and by oxymercuration of 2-cyclohexen-l-ol with mercury(II) trifluoro-acetate in the presence of ehloral and subsequent reduction. ... 

Dihydroxylation of the allyl groups of (70) with hydrogen peroxide and catalytic osmium tetroxide, followed by 0-nitration of the product (72), yields the hexanitrate ester (73). Similar treatment of the mono-allyl ether (74) affords the pentanitrate ester (76). Evans and Callaghan also 0-nitrated the hydroxy groups of (70) and (74) to yield the dinitrate and trinitrate esters, (71) and (75), respectively. The dinitrate ester (71) may find use as a monomer for the synthesis of energetic binders. 

Treatment of porphyrins with hydrogen peroxide and sulfuric acid, or with osmium tetroxide, results in formation of a dihydroxychlorin (44) under acidic conditions these compounds suffer pinacol rearrangement to give compounds, such as (45), known as gemini-ketones (67TL2185,69JCS(C)564). 

Alternatively and more conveniently this ds-hydroxylation process can be effected using only catalytic amounts of osmium tetroxide together with hydrogen peroxide, which cleaves the first formed osmate ester to the diol and regenerates the osmium tetroxide. The reaction is carried out in t-butyl alcohol and is illustrated by the conversion of cyclohexene into ds-cyclohexane-l,2-diol (Expt 5.47). 

Similar results, although with lesser yields, were reported for oxidations with hydrogen peroxide in /erf-butanol in the presence of osmium tetroxide.14 With triacetyl-D-glucal, as well as with free D-glucal, the D-glucose configuration is formed to a greater extent than the D-mannose one. 

Naphthalene oxides. The Diels-Alder reaction of 1,4-diacetoxybutadiene (1) with benzyne (generated from o-benzenediazonium carboxylate, 1, 46) gives the diacetate of l,4-dihydronaphthalene-cis-l,4-diol (2) in 53% yield. The product is converted into 3 by reaction with hydrogen peroxide and catalytic amounts of osmium tetroxide. The monotosylate of 3 is converted into 4 by treatment with base. This epoxy diol has the stereochemistry found in the carcinogenic epoxy diols formed as metabolites of aromatic hydrocarbons. The dimesylate of 3 is converted into the syft-diepoxide 5. 

Cyclopenteaediol isomers have previously been prepared by hydrolysis of acetates produced by reaction of dibromocyclopen-tene with potassiiun acetate in acetic acid by reaction of cyclo-pentene with selenium dioxide in acetic anhydride or by reaction of cyclopentadiene with phenyl iodosoacetate/ with lead tetraacetate, or with peracetic acid in the absence of base. Preparation of cydopentenediol without intermediate formation of acetates has been accomplished by reaction of cyclopentadiene with hydrogen peroxide in the presence of osmium tetroxide in terf-butanol, and hy reaction of cyclopentadiene with peracetic acid in a methylene chloride suspension of anhydrous sodium carbonate, followed by hydrolysis of the resulting epoxycyclo-pentene. ... 

Cyclic osmic esters have long been known to be involved in the osmium tetroxide-catalyzed cis-dihydroxylation of alkenes, but not arenes. The isolation of compound (18) by Wallis and Kochi following irradiation of the charge-transfer complex between osmium tetroxide and benzene is therefore of particular interest. This suggests that the corresponding use of catalytic quantities of osmixim tetroxide in conjunction with hydrogen peroxide could lead to the formation of polyhydroxylated cyclohexenes and -anes. 

The method described is essentially that of Swem, Billen, Findley, and Scanlan. /mM5-l,2-Cyclohexanediol also has been prepared by hydrolysis of cyclohexene oxide. j-l,2-Cydo-hexanediol has been prepared by the reaction of cyclohexene with hydrogen peroxide in tertiary butyl alcohol with osmium tetroxide as a catalyst. Hydrogenation of catechol over Raney nickel catalyst at 150° gives a mixture (m.p. 73-77°) of cis- and trans-1,2-cyclohexanediols. ... 

Osmylation and Epoxidation With osmium tetroxide, carbon nanotubes react as expected for a compound containing double bonds. The osmylation adduct with the respective double bond being replaced by two C-O-bonds is formed as shown in Figure 3.78. However, the process is normally conducted in a photochemical way here. The intermediates thus obtained can be transformed into hydroxylated nanotubes by hydrolysis. In doing so, it is advisable to effect a reoxidation of the resultant osmium(Vl) by hydrogen peroxide in order to minimize the consumption of osmium. The osmylation of carbon nanotubes is reversible so the process may also be employed for purification or separation steps. Contrary to an ozonoly-sis with subsequent reductive work-up, the osmylation does not give rise to holes in the side wall. Hence the electronic structure is less affected. 

OSMIUM(VIII) OXIDE or OSMIUM TETROXIDE (20816-12-0) Contact with hydrochloric acid produces chlorine gas. Explosive reaction with l-methylimidazole. Violent reaction with hydrogen peroxide. Contact with organic and combustible materials may cause fire and explosions. 

The cyclic osmate intermediate is hydrolyzed with hydrogen peroxide that reoxidizes osmium to osmium tetroxide. 

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