Dimethyl sulfoxide, reaction with

The direct oxidative conversion of primary halides or tosylates to aldehydes can be carried out by reaction with dimethyl sulfoxide under alkaline conditions. Formulate a mechanism for this general reaction. 

The methylthiomethyl (MTM) group is a related alcohol-protecting group. There are several methods for introducing the MTM group. Alkylation of an alcoholate by methylthiomethyl chloride is efficient if catalyzed by iodide ion.9 Alcohols are also converted to MTM ethers by reaction with dimethyl sulfoxide in the presence of acetic acid and acetic anhydride10 or with benzoyl peroxide and dimethyl sulfide.11 The latter two methods involve the generation of the methylthiomethylium ion by ionization of an acyloxysulfonium ion (Pummerer reaction). 

The hydroperoxide from the more acidic fluorene prefers to react via the decomposition process (Reaction 6 or 7) rather than the reductive reaction with dimethyl sulfoxide (Reaction 3). 

Polymers. Polyurethane foam has been prepared from the lactose in dried whey by reaction with dimethyl sulfoxide (Hustad et al. 1970). 

Flammable Liquid, Corrosive SAFETY PROFILE Poison by inhalation. Moderately toxic by ingestion. A human systemic irritant by inhalation. Violent hydrolysis reaction with water or steam produces heat, acetic acid, HCl, and other corrosive chlorides. May decompose during preparation. Dangerous fire hazard when exposed to heat or flame. Explosion hazard by spontaneous chemical reaction with dimethyl sulfoxide or ethanol. Also incompatible with PCI3. When heated to decomposition it emits highly toxic fumes of phosgene and Cl . To fight fire, use CO2 or dry chemical. See also CHLORIDES. 

DOT CLASSIFICATION 8 Label Corrosive SAFETY PROFILE Poison by intraperitoneal route. A dangerous storage hazard. It may explode in a sealed botde. Explosive reaction with dimethyl sulfoxide. Reacts vigorously with methyl formamide. When heated to decomposition it emits... 

SAFETY PROFILE Confirmed carcinogen with experimental tumorigenic data by skin contact. Human systemic effects by inhalation unspecified effects on olfaction and respiratory systems. Corrosive effects on the skin, eyes, and mucous membranes by inhalation. Flammable when exposed to heat or flame. Will react with water or steam to produce heat and toxic and corrosive fumes. Violent or explosive reaction with dimethyl sulfoxide, and aluminum chloride + naphthalene. To fight fire, use alcohol foam, CO2, dry chemical. Incompatible with dimethyl sulfoxide, (NaNs + KOH), water, steam, and oxidizers. When heated to decomposition it emits toxic fumes of CT, See also CHLORIDES and ALDEHYDES. 

The reaction with dimethyl sulfoxide provides a useful method of oxidizing an alkyl halide to a ketone. Thiols are powerful nucleophiles and displace alkyl halides. 

Barton devised a new method for the oxidation of primary alcohols to aldehydes involving in the first step conversion to the alkyl chloroformate (1) by adding a solution of the alcohol in ether to ether saturated with phosgene (15-20% w./v.) the solvent is removed at reduced pressure. If the alcohol is hindered, quinoline is added as catalyst and the quinoline hydrochloride removed by filtration. The next step, reaction with dimethyl sulfoxide, is attended with evolution of carbon... 

SULFURIC ACID, BARIUM SALT (7727-43-7) BaS04 Noncombustible solid. An oxidizer. Violent reaction with dimethyl sulfoxide, sodium acetylide, finely divided carbon, aliuninum, magnesium, zirconium, and possibly other active metals, especially in the presence of elevated temperatures. Incompatible with reducing agents aluminmn, potassium, phosphorus. When heated to decomposition, forms toxic sulfur oxides. 

Introduction of the oxygen atom presumably occurred through reaction with dimethyl sulfoxide acting as a nucleophile and displacing a chlorine in 16. A mechanistic rationale involving such an attack was proposed and is outlined in Scheme 7 <2000J(P1)1081>. 

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