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Dimethyl sulfoxide/oxalyl chloride

Quebrachitol was converted into iL-c/j/roinositol (105). Exhaustive O-isopropylidenation of 105 with 2,2-dimethoxypropane, selective removal of the 3,4-0-protective group, and preferential 3-0-benzylation gave compound 106. Oxidation of 106 with dimethyl sulfoxide-oxalyl chloride provided the inosose 107. Wittig reaction of 107 with methyl(triphenyl)phos-phonium bromide and butyllithium, and subsequent hydroboration and oxidation furnished compound 108. A series of reactions, namely, protection of the primary hydroxyl group, 0-debenzylation, formation of A-methyl dithiocarbonate, deoxygenation with tributyltin hydride, and removal of the protective groups, converted 108 into 7. [Pg.40]

Halogenation of 106 with triphenylphosphine, iodine, and imidazole provided the iodo derivative 109. On treatment with lithium aluminum hydride, 109 was converted into two endocyclic alkenes, 110 and di-O-isopro-pylidenecyclohexanetetrol, in the ratio of 2 1. Oxidation of 110 with dimethyl sulfoxide - oxalyl chloride afforded the enone 111.1,4-Addition of ethyl 2-lithio-l,3-dithiane-2-carboxylate provided compound 112. Reduction of 112 with lithium aluminum hydride, and shortening of the side-chain, gave compound 113, which was converted into 114 by deprotection. ... [Pg.40]

The reaction of the aldehyde 174, prepared from D-glucose diethyl dithio-acetal by way of compounds 172 and 173, with lithium dimethyl methyl-phosphonate gave the adduct 175. Conversion of 175 into compound 176, followed by oxidation with dimethyl sulfoxide-oxalyl chloride, provided diketone 177. Cyclization of 177 with ethyldiisopropylamine gave the enone 178, which furnished compounds 179 and 180 on sodium borohydride reduction. 0-Desilylation, catalytic hydrogenation, 0-debenzyIation, and acetylation converted 179 into the pentaacetate 93 and 5a-carba-a-L-ido-pyranose pentaacetate (181). [Pg.48]

Fluoroalkylatcd diazirines are an interesting class of compounds that are prepared from the corresponding diaziridincs. Thus, the oxidation of 3-aryl-3-(lrifluoromethyl)diaziridine (t) to diazirine 2 is carried out with a mixture of dimethyl sulfoxide/oxalyl chloride in good yields.256 This gentle oxidation does not affect the sulfur in 2-thienyl aziridines. Similarly, the oxidation of diaziridine 3 to bis(Lrifluoromethyl)diazirine 4 is accomplished using lead(IV) acetate.244 This diazirine can be stored in a steel cylinder at 25r C and shows no tendency to detonate. [Pg.65]

Dimethyl sulfoxide-oxalyl chloride, 215-216 Dimethyl sulfoxide-sulfur trioxide, 216 Dimethyl(2,4,6-tri-f-butylphenoxy)chlorosilanc. 217... [Pg.334]

J-KETO ESTERS Dimethyl sulfoxide-Oxalyl chloride. Mercury(II) oxide-Boron trifluoride. [Pg.651]

Huang, S. L., Swern, D. Preparation of iminosulfuranes utilizing the dimethyl sulfoxide-oxalyl chloride reagent. J. Org. Chem. 1978, 43, 4537 538. [Pg.692]

Dimethyl sulfoxide-Oxalyl chloride, 167 Dimethyl sulfoxide-Trifluoroacetic anhydride, 168... [Pg.261]

A few years later the Swem laboratory then developed an activator which they claimed to be the most successful in activating dimethyl sulfoxide toward oxidation, namely, oxalyl chloride. Since oxalyl chloride reacted violently and exothermically with dimethyl sulfoxide, successful activation required the use of low temperatures to form the initial intermediate.6 Swem et al. reported the oxidation of long chain primary alcohols to aldehydes which was previously unsuccessful by first converting to the sulfonate ester (either mesylate or tosylate) and then employing the dimethyl sulfoxide-acetic anhydride procedure. They found that long-chain saturated, unsaturated, acetylenic and steroidal alcohols could all be oxidised with dimethyl sulfoxide-oxalyl chloride in high yields under mild conditions. [Pg.292]

Dichloro-5,6-dicyan o-l, 4-benzo-quinone. Dimethyl selenoxide. Dimethyl sulfoxide-Oxalyl chloride. [Pg.276]

The reaction of dimethyl sulfoxide, oxalyl chloride and an alcohol is normally carried out at -78 or —60 °C, since the formation of the alkoxysulfonium salt 29 is rapid at this low temperature. After addition of the base triethylamine, the mixture may be warmed to —30 °C or higher to promote proton abstraction and fragmentation. The use of diisopropylethylamine instead of triethylamine as the base or addition of pH 7 phosphate buffer can, in the rare cases when it does occur, reduce the extent of enoUzation and therefore minimize any racemization or rearrangement of p,7-double bonds. [Pg.383]

Related Reagents. Dimethyl Sulfoxide-Oxalyl Chloride Oxalyl Chloride-Aluminum Chloride. [Pg.286]

Oxidations of alcohols using the dimethyl sulfoxide-oxalyl chloride combination are known as Swern oxidations after Daniel Swern of Temple University who developed the method. [Pg.664]

Oxidation of an Alcohol with Dimethyl Sulfoxide —Oxalyl Chloride (Swern Oxidation)... [Pg.1329]

Related Reagents. 7V-Bromosuccinimide Chloramine-T 7V-Chlorosuccinimide N-(l, 1-Dimethylethyl)benzenesulfinimi-doyl Chloride Tetrapropylammonium Perruthenate Dimethyl sulfoxide-oxalyl Chloride l,l,l-Triacetoxy-l,l-dihydro-l,2-benziodoxol-3(l/7)-one 2-Iodoxybenzoic Acid (IBX) Diphenyl Sulfoxide. [Pg.217]

Related Reagents. Dimethyl Sulfoxide-Acetic Anhydride Dimethyl Sulfoxide-Dicyclohexylcarbodiimide Dimethyl Sulfoxide-Methanesulfonic Anhydride Dimethyl Sulfoxide-Oxalyl Chloride Dimethyl Sulfoxide-Phosgene Dimethyl Sulfoxide-Phosphorus Pentoxide Dimethyl Sulfoxide-Sulfur Trioxide/Pyridine Dimethyl Sulfoxide-Tiifluoroacetic Anhydride Dimethyl Sulfoxide-Triphosgene. [Pg.233]

Related Reagents. A/-Chlorosuccinimide-Dimethyl Sulfide Chromic Acid Dimethyl Sulfide-Chlorine Dimethyl Sulfoxide-Acetic Anhydride Dimethyl Sulfoxide-Dicyclo-hexylcarbodiimide Dimethyl Sulfoxide-Oxalyl Chloride Dimethyl Sulfoxide-Phosphorus Pentoxide Dimethyl Sulfoxide-Sulfur Trioxide/Pyridine Dimethyl Sulfoxide-Trifluoroacetic Anhydride Dimethyl Sulfoxide-Triphosgene Manganese Dioxide Pyridinium Chlorochromate Pyridinium Dichromate Ruthenium(rV) Oxide Silver(I) Carbonate on Celite 1,1,1-Triacetoxy-1,1-dihydro-1,2-benziodoxol-3( 1 H)-ons. [Pg.234]


See other pages where Dimethyl sulfoxide/oxalyl chloride is mentioned: [Pg.150]    [Pg.150]    [Pg.167]    [Pg.179]    [Pg.450]    [Pg.648]    [Pg.149]    [Pg.149]    [Pg.301]    [Pg.301]    [Pg.571]    [Pg.1051]    [Pg.355]    [Pg.60]    [Pg.180]    [Pg.301]    [Pg.465]    [Pg.235]    [Pg.237]   
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See also in sourсe #XX -- [ Pg.167 ]

See also in sourсe #XX -- [ Pg.225 ]

See also in sourсe #XX -- [ Pg.149 ]

See also in sourсe #XX -- [ Pg.225 ]

See also in sourсe #XX -- [ Pg.200 ]

See also in sourсe #XX -- [ Pg.309 , Pg.410 ]




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2.5- dimethyl- -chloride

Oxalyl

Sulfoxides dimethyl

Sulfoxides dimethyl sulfoxide

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