67-68-5 Dimethylsulfoxide

The powerful solvent properties of dimethylsulfoxide (DMSO), for example, are used to dissolve selectively the polynuclear aromatics found in oils and paraffins. The procedure is shown in Figure 2.5. 

Design Institute for Physical Property Data dimethylformamide dimethylsulfoxide I distribution octane number Economic Commission for Europe j European Economic Community i (Communaute Economique Europeenne)... 

METHOD 2 Speed chemists have used hydroiodic acid (HI) for years to reduce ephedrine to meth. So when the government placed HI on the restricted list, speed chemists took to making the HI themselves. One of the ways they used was to make Hi in DMSO (dimethylsulfoxide, a common solvent) by reacting Nal or Kl with sulfuric acid. This a standard way to make both HBr or Hi in water (see the Chemicals section of this book) except these speed chemists were using the non-aqueous solvent DMSO instead of water. 

METHOD 3 Things start to look easier and the yields higher when the following method is employed [122]. This method uses a solvent called DMSO (dimethylsulfoxide). Maybe you ve never heard of this solvent but Strike has. It is a common solvent used in all fields of science and although Strike is not 100% sure. Strike believes that one can substitute DMF (dimethylformanilide) for DMSO. 

THF, tetrahydrofuran DMSO. dimethylsulfoxide TEA, triethylamine DMF. dimethyl-formamid. 

Methyl free radicals, generated either by thermolysis of lead tetracetate in acetic acid solution (401) or by radical cleavage of dimethylsulfoxide by H2O2 and iron (II) salts (408), afford 2- and 5-methylthiazole in the proportion of 86 and 14%, respectively, in agreement with the nucleophilic character of alkyl free radicals and the positive charge of the 2-carbon atom of the thiazole (6). 

Dimethylsulfoxide. Glacial acetic acid. Acetonitrile. Acetone10% water. 

Dimethylsulfoxide Acyl and aryl halides, boron compounds, bromomethane, nitrogen dioxide, magnesium perchlorate, periodic acid, silver difluoride, sodium hydride, sulfur trioxide... 

Phosphorus trichloride Acetic acid, aluminum, chromyl dichloride, dimethylsulfoxide, hydroxylamine, lead dioxide, nitric acid, nitrous acid, organic matter, potassium, sodium water... 

Phosphoryl chloride Carbon disulflde, A,A-dimethylformamide, 2,5-dimethylpyrrole, 2,6-dimethyl-pyridine 1-oxide, dimethylsulfoxide, water, zinc... 

Sulfuryl dichloride Alkalis, diethyl ether, dimethylsulfoxide, dinitrogen tetroxide, lead dioxide, phosphorus... 

Thionyl chloride Ammonia, dimethylsulfoxide, linseed oil, quinoline, sodium... 

This can be recrystallized from dimethylsulfoxide to give well-defined leaflets. 

Figure 6-2. Curved Arrhenius plot for the hydrolysis of methyl trifluoroacetate in dimethylsulfoxide-water (mole fraction water = 0.973). ...

The curvature may be an artifact of a selection of nucleophiles of mixed structural types chosen to display a wide range in pAo. Buncel et al. ° varied pK by changing the solvent composition over a limited range rather than by changing the structure. They studied the reaction between X-C6H4-CT and p-nitrophenyl acetate in 40-90 mol% dimethylsulfoxide—water mixtures with just three X substituents... 

We consider first the Sn2 type of process. (In some important Sn2 reactions the solvent may function as the nucleophile. We will treat solvent nucleophilicity as a separate topic in Chapter 8.) Basicity toward the proton, that is, the pKa of the conjugate acid of the nucleophile, has been found to be less successful as a model property for reactions at saturated carbon than for nucleophilic acyl transfers, although basicity must have some relationship to nucleophilicity. Bordwell et al. have demonstrated very satisfactory Brjinsted-type plots for nucleophilic displacements at saturated carbon when the basicities and reactivities are measured in polar aprotic solvents like dimethylsulfoxide. The problem of establishing such simple correlations in hydroxylic solvents lies in the varying solvation stabilization within a reaction series in H-bond donor solvents. 

The coordination number of Ni rarely exceeds 6 and its principal stereochemistries are octahedral and square planar (4-coordinalc) with rather fewer examples of trigonal bipyramidal (5), square pyramidal (5), and tetrahedral (4). Octahedral complexes of Ni arc obtained (often from aqueous solution by replacement of coordinated water) especially with neutral N-donor ligands such as NH3, en, bipy and phen, but also with NCS, N02 and the 0-donor dimethylsulfoxide. dmso (Me2SO). 

An inert solvent such as benzene, toluene or xylene, or an excess of the alcohol corresponding to the alkoxide is often used as solvent. When a dipolar aprotic solvent such as A,A-dimethylformamide (DMF) or dimethylsulfoxide (DMSO) is used, the reaction often proceeds at higher rate. 

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