Tetramethylene sulfone

Perfluorosulfonyl fluorides have also been prepared by dkect fluotination, although ki general yields are lower than preparation by ECF. Perfluoromethanesulfonyl fluoride has been produced ki 15% yield from dkect fluotination of dimethyl sulfone (16). Perfluoro-2-propanesulfonyl fluoride was prepared ki 29% yield from propanesulfonyl fluoride (17). Dkect fluotination of tetramethylene sulfone leads to the kitact perfluorkiated sulfone ki 28% yield and the ting-opened product (perfluorobutanesulfonyl fluoride) ki 10% yield (eq. 10) (17). 

Nitrations can be performed in homogeneous media, using tetramethylene sulfone or nitromethane (nitroethane) as solvent. A large variety of aromatic compounds have been nitrated with nitronium salts in excellent yields in nonaqueous media. Sensitive compounds, otherwise easily hydroly2ed or oxidized by nitric acid, can be nitrated without secondary effects. Nitration of aromatic compounds is considered an irreversible reaction. However, the reversibihty of the reaction has been demonstrated in some cases, eg, 9-nitroanthracene, as well as pentamethylnitrobenzene transnitrate benzene, toluene, and mesitylene in the presence of superacids (158) (see Nitration). 

Properties. Sulfolane [126-33-0] C4HgS02 (1), also known as tetrahydrothiophene-1,1-dioxide and tetramethylene sulfone, is a colorless, highly polar, water-soluble compound. Physical properties are given ia Table 1 (1). 

As normally polymerized, PVF melts between IH5 and 210 °C and contains 12 18% inverted monomer units ft is normally considered a thermoplastic, but because of its instability above its melting point, it cannot be processed by conventional thermoplastic techniques Instead it is generally extruded into films in a solvent swollen (organosol) form and the solvent is subsequently evaporated and recovered Such films can be onented further to achieve specific mechanical properties PVF films are exceptionally weather and radiabon resistant considenng their modest fluonne content PVF is insoluble below 100 °C but, at higher temperatures, it dissolves in polar solvents like amides, ketones, tetramethylene sulfone, and tetramethylurea Resistance to acids and bases at room temperature IS good [1, 29 ... 

The importance of the solvent, in many cases an excess of the quatemizing reagent, in the formation of heterocyclic salts was recognized early. The function of dielectric constants and other more detailed influences on quatemization are dealt with in Section VI, but a consideration of the subject from a preparative standpoint is presented here. Methanol and ethanol are used frequently as solvents, and acetone,chloroform, acetonitrile, nitrobenzene, and dimethyl-formamide have been used successfully. The last two solvents were among those considered by Coleman and Fuoss in their search for a suitable solvent for kinetic experiments both solvents gave rise to side reactions when used for the reaction of pyridine with i-butyl bromide. Their observation with nitrobenzene is unexpected, and no other workers have reported difficulties. However, tetramethylene sulfone, 2,4-dimethylsulfolane, ethylene and propylene carbonates, and salicylaldehyde were satisfactory, giving relatively rapid reactions and clean products. Ethylene dichloride, used quite frequently for Friedel-Crafts reactions, would be expected to be a useful solvent but has only recently been used for quatemization reactions. ... 

Liquid solvents are used to extract either desirable or undesirable compounds from a liquid mixture. Solvent extraction processes use a liquid solvent that has a high solvolytic power for certain compounds in the feed mixture. For example, ethylene glycol has a greater affinity for aromatic hydrocarbons and extracts them preferentially from a reformate mixture (a liquid paraffinic and aromatic product from catalytic reforming). The raffinate, which is mainly paraffins, is freed from traces of ethylene glycol by distillation. Other solvents that could be used for this purpose are liquid sulfur dioxide and sulfolane (tetramethylene sulfone). 

Sulfolane (tetramethylene sulfone) is produced hy the reaction of butadiene and sulfur dioxide followed hy hydrogenation ... 

B. 3,5-Dinilro-o-tolunitrile. A 500-ml. four-necked flask is equipped with a mechanical stirrer, a dropping funnel, a thermometer, and an inlet for dry nitrogen (Note 13). It is baked thoroughly by means of a Bunsen flame and allowed to cool to room temperature with a slow stream of dry nitrogen passing through it. The flask is charged, preferably in a dry box, with 335 g. of tetramethylene sulfone (Note 14) and 73.1 g. (0.55 mole) of nitronium tetrafluoroborate. The thermometer is adjusted so... 

Tetramethylene sulfone is commercially available from the Shell Chemical Company and the Phillips Petroleum Company. 

A saturated solution at 25° contains 7 g. of nitronium tetrafluoroborate per 100 g. of tetramethylene sulfone. 

Introduction of a sulfur atom into saturated hydrocarbons leads to a considerable decrease, by an order of magnitude, in the yield of radicals [G(radicals) for hydrocarbons 420]. This was explained as due to the existence of low-lying d-orbitals at the sulfur atom. This explanation agrees with the observation that this decrease is smaller in the case of insertion of a SO group, as there are four p electrons of the S atoms which may be excited at the d-orbital for sulfide and only two p electrons in the case of sulfoxides. Additional proof is that for sulfones, where there is no available p electron, the yield of the radicals [G(radicals) = 3.7 for tetramethylene sulfone] is about the same as for hydrocarbons. 

The apparatus consists of a 2-1., three-necked, round-bottomed flask equipped with a mechanical stirrer, a pressure-equalized dropping funnel through which dry nitrogen can be added, and a reflux condenser, and is to be maintained at 0°. The outlet tube on the reflux condenser leads to a large U-tube trap, fitted with stopcocks on both sides, and immersed in a Dry Ice-isopropyl alcohol bath. The U-trap vents to a mineral oil bubbler. (See Fig. 17.) Sodium fluoride, 454 g. (10.8 mols) is added to the flask followed by approximately 1200 ml. of tetramethylene sulfone. The system is then flushed thor-... 

Sulfolane A process for removing aromatic hydrocarbons from petroleum fractions by liquid-liquid extraction using sulfolane (tetramethylene sulfone tetrahydrothiophene-1,1-dioxide) at approximately 190°C. Developed by Shell Development Company in 1959 and first commercialized in 1962 now licensed through UOP. It replaced the Udex process. Sulfolane is used for another purpose in the Sulfinol process. 

Starting materials which are only sparingly soluble in water may require solvents that are either partially or entirely organic. Diazotization can either be carried out as usual with an aqueous sodium nitrite solution, or alternatively with nitrosylsul-furic acid or an organic nitrite. Appropriate solvents must be stable to the reactants. Examples include aromatic hydrocarbons, chlorohydrocarbons, glycol ethers, nitriles, esters, and dipolar aprotic solvents, such as dimethyl formamide, dimethyl sulfone, tetramethylene sulfone, tetramethyl urea, and N-methylpyrroli-done. 

In most other cases the relationship will allow the approximate prediction of the half-wave potentials of a given ion in a solvent of given donicity by interpolation. It may be expected that E jy2 for a certain metal ion in tetramethylene sulfone (DN = 14.8) will be similar to that in PDC (DN = 15.1), benzylcyanide (DN = 15.1) or ethylene sulfite (DN = 15.3). Likewise, the half-wave potentials are expected to be similar in nitrobenzene (DN = 4.4) and nitromethane (DN = 2.7). In an analogous manner the half-wave potentials may be predicted in methyl acetate, diethylether, pyridine, and various other solvents. 

According to ESR spectra, cyclobutanone and tetramethylene sulfone undergo dissociative electron capture process (Scheme 3.34 for cyclobutanone) in argon matrices and yield distonic anion-radicals (Kasai 1991, Koeppe and Kasai 1994). 

The preparation of oxazolines from p-hydroxy amides and SOCI2 via the corresponding p-chloro amides under basic conditions is well known and has been discussed earlier. Potassium fluoride on alumina has been reported as a mild alternative to the aqueous or alcoholic bases that are commonly used. The reaction is typically carried out in acetonitrile or tetramethylene sulfone and moderate to good yields of oxazolines and oxazines can be obtained as shown in Scheme 8.29. 

Fluorination of perchloro bis(imine) 4 with sodium fluoride in tetramethylene sulfone at 120 JC takes place with ring formation to give the perfluoro imidazole derivatives 5-7.13... 

Trifluoro-l,3,5-triazine (13) is prepared from 2,4,6-trichloro-l,3,5-triazine (12) and sodium fluoride in refluxing tetramethylene sulfone and distilling out the product as it is formed (bp 72.5-73.5cC/760 Torr).11... 

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