Diols with dimethyl sulfoxide

Gillis and Beck heated the 1,4-diol (1) with dimethyl sulfoxide in the hope of obtaining the conjugated diene but found the product to be the cyclic oxide (2). 

Oxidative cleavage of an alkene with ozone leads to an ozonide. Reductive workup with dimethyl sulfoxide or zinc and acetic acid gives ketones and/or aldehydes. Oxidative workup with hydrogen peroxide gives ketones and/or carboxylic acids. Oxidative cleavage of 1,2-diols with periodic acid or with lead tetraacetate gives aldehydes or ketones. 

Columns can be washed with solvents and solvent combinations suitable to remove adsorbed contaminants. When considering the adsorption of analytes, think not only of the diol functionality, but also of the adsorption to residual silanols. Often, the injection of small amounts (500 /d) of dimethyl sulfoxide removes contamination that has accumulated on the column. Aqueous solutions of sodium dodecyl sulfate, guanidine hydrochloride, or urea are compatible with Protein-Pak columns. 

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). 

The hydrolysis of epoxides is a convenient method for the preparation of vie-diols. The reaction is catalyzed by acids or bases (see discussion of the mechanism on p. 369). Among acid catalysts the reagent of choice is perchloric acid, since side reactions are minimized with this reagent.500 Dimethyl sulfoxide is a superior solvent for the alkaline hydrolysis of epoxides.501 OS V, 414. 

There are several methods reported in the literature for transforming vicinal diols into ct-diketones while avoiding the risk of C-C bond cleavage.26 Examples include the standard Swem conditions (dimethyl sulfoxide and oxalyl chloride followed by triethylamine), or the use of DMSO activated by acetic anhydride, pyridine-sulfur trioxide complex, or dicyclohexylcarbodiimide (Mq/J-att oxidation). Diones are also obtained by treatment with benzalacetone as a hydride acceptor in the presence of catalytic amounts of tris(triphenylphosphine)ruthenium dichlonde [(PPh RuCFl.27 Recent developments include the use of w-iodoxyben/.oic acid28 or the oxoammonium salt of 4-acctamidoletramethylpipcridine-1-oxyl and y -toluencNulfonic acid.29... 

Sutton [1.15] studied the question of how quickly solutions with certain CPAs [GL, dimethyl sulfoxide (DMSO) and others] have to be cooled in order to avoid crystallization. At 100 °C/min, concentrations of 42.1% DMSO and 48.5% GL are necessary to achieve the glass phase. With a 32.5% solution of (2R,3P)-(-)-butane-2,3-diol, the same effect can be accomplished at 50°C/min. Sutton showed (see Figure 1.18) that polyethylene glycol with a molecular weight of 400 (PEG 400) reduced the critical cooling rate to -25 °C/min. The addition of PEG 8000 [1.115] improved the protection of lactate dehydrogenase (LDH) by maltodextrins, if maltodextrins with low dextrose equivalents are used. 

The A -nitroso compound (179) was equilibriated with rert-butoxide-dimethyl sulfoxide to the trans-cis mixture which was denitrosated over Raney nickel and hydrolyzed to yield a mixture of diols (180). Refluxing 180 in ethyl orthoformate resulted in isolation of the crystalline amidoacetal which exhibited IR and NMR spectra identical to those of the amidoacetal... 

Two syntheses of racemic 2,3-dihydrotriquinacen-2-one (380) have been described. The first approach consisted in the selective monoketalization of diketone 364 with 2,2-dimethylpropane-l, 3-diol and Baeyer-Villiger oxidation of 375 (Scheme 60).357 Although two lactones were produced, 376 could be freed of its isomer by selective alkaline hydrolysis. Diisobutylalumium hydride reduction of 376 afforded 377, the acetate of which was converted by acid treatment to 378. Ketaliza-tion of this isomeric mixture, followed by hydrolysis, mesylation, and treatment with potassium f-butoxide in dimethyl sulfoxide afforded diene ketal 379. Deketa-lization then liberated the desired ketone. 

In an example of the use of this activation method testosterone, with a IT -hydroxy group, was oxidized to A -androstene-3,17-dione very rapidly in high yield, in contrast to the use DMSO-acetic anhydride. During a reaction, when other oxidizing agents were found to be ineffective, sulfur trioxide/dimethyl sulfoxide led to smooth oxidation of the df-diol (16 equation 8) to an o-quinone in 49% yield and the ci.r-diol (17) to (18 equation 9) in 98% yield. - The use of dimethyl sulfoxide-acetic anhydride for this oxidation gave large amounts of the diacetate as the by-product. 

The oxidation of diols having alcoholic groups of the same nature, for example, both alcoholic groups are primary, secondary, allylic, or benzylic, is usually carried out at both groups to yield dialdehydes [832] or diketones [552], Such reactions are achieved by chromium trioxide [582], barium manganate [832], dimethyl sulfoxide activated with acetic anhydride [1013], and others (equations 284 and 285). 

The solvent properties of alcohols with short carbon chains are similar to those of water and such alcohols could be used as the nonaqueous catalyst phase when the products are apolar in nature. The first commercial biphasic process, the Shell Higher Olefin Process (SHOP) developed by Keim et al. [4], is nonaqueous and uses butanediol as the catalyst phase and a nickel catalyst modified with a diol-soluble phosphine, R2PCH2COOH. While ethylene is highly soluble in butanediol, the higher olefins phase-separate from the catalyst phase (cf. Section 2.3.1.3). The dimerization of butadiene to 1,3,7-octatriene was studied using triphenylphosphine-modified palladium catalyst in acetonitrile/hexafluoro-2-phe-nyl-2-propanol solvent mixtures [5]. The reaction of butadiene with phthalic acid to give octyl phthalate can be catalyzed by a nonaqueous catalyst formed in-situ from Pd(acac)2 (acac, acetylacetonate) and P(0CeH40CH3)3 in dimethyl sulfoxide (DMSO). In both systems the products are extracted from the catalyst phase by isooctane, which is separated from the final products by distillation [5]. 

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