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Polyaryl sulfoxides

Solvent for Displacement Reactions. As the most polar of the common aprotic solvents, DMSO is a favored solvent for displacement reactions because of its high dielectric constant and because anions are less solvated in it (87). Rates for these reactions are sometimes a thousand times faster in DMSO than in alcohols. Suitable nucleophiles include acetyUde ion, alkoxide ion, hydroxide ion, azide ion, carbanions, carboxylate ions, cyanide ion, hahde ions, mercaptide ions, phenoxide ions, nitrite ions, and thiocyanate ions (31). Rates of displacement by amides or amines are also greater in DMSO than in alcohol or aqueous solutions. Dimethyl sulfoxide is used as the reaction solvent in the manufacture of high performance, polyaryl ether polymers by reaction of bis(4,4 -chlorophenyl) sulfone with the disodium salts of dihydroxyphenols, eg, bisphenol A or 4,4 -sulfonylbisphenol (88). These and related reactions are made more economical by efficient recycling of DMSO (89). Nucleophilic displacement of activated aromatic nitro groups with aryloxy anion in DMSO is a versatile and useful reaction for the synthesis of aromatic ethers and polyethers (90). [Pg.112]

Dimethyl sulfoxide is used as a reaction solvent in the polymerization of acrylonitrile with a vinyl monomer (e.g., styrene) [2,3]. Reaction of diisocyanates and polyols or polyamines dissolved in DMSO yield solutions of the polyurethanes [4]. Mixtures of DMSO and water are used as a spinning solvent for polymer fibers. Polyaryl ether polymers are formed from DMSO... [Pg.286]


See also in sourсe #XX -- [ Pg.249 ]




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