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Dimethyl sulfoxide periodate oxidation

See Periodic acid Dimethyl sulfoxide Phosphorus(III) oxide... [Pg.347]

A. 1 -Phenyl-3-butyh-1 -ol (1) (Note 1). A 1000-mL, oven-dried, three-necked, round-bottomed flask is equipped with a magnetic stir bar and pressure-equalizing addition funnel, fitted with a rubber septum, and placed under an argon atmosphere. The flask is charged with lithium acetylide-ethylenediamine complex (50 g, 543 mmol) (Note 2), which is dissolved in anhydrous dimethyl sulfoxide (360 mL) (Note 3) with stirring. The flask is placed in a room temperature water bath (Note 4), the addition funnel is charged with styrene oxide (42.0 mL, 368 mmol) (Note 5), and styrene oxide is added dropwise over a period of approximately 5 min. The reaction mixture is stirred for 2 hr and quenched by... [Pg.161]

In 1967 Cava and Pollack obtained derivatives of the fourth, so-called nonclassical , thienothiophene— thieno[3,4-c]thiophene (4), a condensed heterocycle with formdly tetracovalent sulfur (42)j. The reaction of 3,4-bischloromethyl-2,5-dimethylthiophene (141) with sodium sulfide afforded 4,6-dimethyl-lif,3ff-thieno[3,4-c]thiophene (142) periodate oxidation of 142 gave die corresponding sulfoxide (143) in 91% yield. Attempts to convert the sulfoxide (143) into the thieno-[3,4-c]thiophene by the method used for S3mthesizing benzo[c]-thiophene led only to polymer. However, 24% of adduct 144 and 10% of 145 were obtained by refluxing sulfoxide (143) with N-phenylmaleimide in acetic anhydride, indicating that the thieno[3,4-c]-thiophene was formed as an intermediate. [Pg.152]

Reduction of the furan (152) with sodium borohydride gave diol 154 and its cyclization (P2SJ/CS2) formed 19% of sulfide (155). Periodate oxidation of 155 gave (92%) the corresponding sulfoxide (156). The latter reacted with dimethyl acetylenedicarboxylate forming the adduct 157 (70%) the formation of 157 is evidence of the presence of the thieno[3,4-c]furan system (158) as an intermediate. Cyclization of diketone 153 in the presence of phosphorus pentasulfide proceeds M. P. Cava and M. A. Sprecker, J. Amer. Chem. Soc. 94, 6214 (1972). [Pg.154]

Periodate oxidation is generally performed in aqueous solution, but Yu and Bishop studied oxidation with periodic acid in dimethyl sulfoxide.81 They observed limited oxidation, probably attributable to rapid formation of hemiacetals. Concentrated solutions of periodic acid in dimethyl sulfoxide may explode 82 therefore, only dilute solute) T. Painter and B. Larsen, A eta Chem. Scand., 24, 2366-2378 (1970). [Pg.201]

Woods contain a number of acyl (mainly acetyl) groups, and it is probable that these are associated with the xylan components of the hemicellulose fraction. Evidence for the original esterification of aspen-wood xylan comes from the observation that the isolated xylan (obtained by alkaline extraction) is readily cleaved by periodate, whereas only a small proportion of the D-xylose residues in the wood itself are oxidized under similar conditions.66 Hemicelluloses still containing acyl groups may be extracted from wood holocelluloses by means of dimethyl sulfoxide, and further quantities... [Pg.462]

Diarylacetylenes are converted in 55-90% yields into a-diketones by refluxing for 2-7 h with thallium trinitrate in glyme solutions containing perchloric acid [413. Other oxidants capable of achieving the same oxidation are ozone [84], selenium dioxide [509], zinc dichromate [660], molybdenum peroxo complex with HMPA [534], potassium permanganate in buffered solutions [848, 856, 864,1117], zinc permanganate [898], osmium tetroxide with potassium chlorate [717], ruthenium tetroxide and sodium hypochlorite or periodate [938], dimethyl sulfoxide and iV-bromosuccin-imide [997], and iodosobenzene in the presence of a ruthenium catalyst [787] (equation 143). [Pg.91]

The oxidative cleavage of epoxides with hydrogen peroxide gives vicinal hydroxy hydroperoxides [178]. With dimethyl sulfoxide in the presence of trifluoromethanesulfonic acid and diisopropylethylamine, epoxides are converted into a-hydroxy ketones [1014], and with periodic acid, dicarbonyl compounds are formed [761] (equations 343 and 344). [Pg.173]

Potassium permanganate. Dimethyl sulfide-Chlorine. Dimethyl sulfoxide. Dimethyl sulfoxide-Chlorine. Dimethylsulf-oxide Sulfur trioxide. Dipyridine chro-mium(VI) oxide. Iodine. Iodine-Potassium iodide. Iodine tris(trifluoroacetate). Iodosobenzene diacetate. Isoamyl nitrite. Lead tetraacetate. Manganese dioxide. Mercuric acetate. Mercuric oxide. Osmium tetroxide—Potassium chlorate. Ozone. Periodic acid. Pertrifluoroacetic acid. Potassium ferrate. Potassium ferricyanide. Potassium nitrosodisulfonate. Ruthenium tetroxide. Selenium dioxide. Silver carbonate. Silver carbonate-Celite. Silver nitrate. Silver oxide. Silver(II) oxide. Sodium hypochlorite. Sulfur trioxide. Thalli-um(III) nitrate. Thallium sulfate. Thalli-um(III) trifluoroacetate. Triphenyl phosphite ozonide. Triphenylphosphine dibromide. Trityl fluoroborate. [Pg.297]

Dimethyl sulfoxide-Sulfur trioxide [1, 309, before references]. The combination of DMSO and sulfur trioxide, in the form of the pyridine complex, in the presence of trimethylamine oxidizes primary and secondary alcohols in good yield to aldehydes and ketones, respectively.55 The reaction usually is complete within minutes and the products are isolated by acidification and precipitation with water. The reagent also oxidizes allylic alcohols to the corresponding a,fi-unsaturated carbonyl compounds. One advantage over the DMSO-DCC method is that the elaborate purification required when dicyclohexylurea is a product can be dispensed with. Testosterone, with a 17/3-hydroxyl group, was oxidized toA -androstene-3,17-dione very rapidly the 17-epimer required a period of 35 min. [Pg.359]

Decarboxylation /-Butylhydroperoxide. Copper powder. Dimethyl sulfoxide. Iron. Decarboxylation, oxidative Lead dioxide. Lead tetraacetate. Pyridine-N-oxide. Degradation, bile acid side chain Periodic acid. [Pg.513]

DIMETHYL SULFOXIDE (67-68-5) Forms explosive mixture with air (flash point 203°F/95°C oc). Violent or explosive reaction with oxidizers, acryl halides, aryl halides and related compounds, p-bromobenzoyl acetanilide, boron compounds, iodine pentafluoride, magnesium perchlorate, methyl bromide, perchloric acid, periodic acid, silver fluoride, sodium hydride, potassium permanganate. Forms powerfully explosive mixtures with metal salts of oxoacids. [Pg.460]


See other pages where Dimethyl sulfoxide periodate oxidation is mentioned: [Pg.654]    [Pg.853]    [Pg.853]    [Pg.254]    [Pg.298]    [Pg.109]    [Pg.194]    [Pg.571]    [Pg.1081]    [Pg.1051]    [Pg.586]    [Pg.655]    [Pg.884]    [Pg.1390]    [Pg.1774]    [Pg.515]    [Pg.179]    [Pg.400]    [Pg.409]    [Pg.835]    [Pg.476]    [Pg.782]    [Pg.344]    [Pg.258]    [Pg.195]    [Pg.194]    [Pg.220]   


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6,6-Dimethyl 1-oxid

Dimethyl sulfoxide oxidations

Oxidants periodate

Period 3 oxides

Periodate oxidation

Sulfoxide oxidation

Sulfoxides dimethyl

Sulfoxides dimethyl sulfoxide

Sulfoxides oxidation

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