REACTIONS THOUSANDS OF TIMES FASTER IN DMSO! - C&EN

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REACTIONS THOUSANDS OF T I M E S F A S T E R I N DMSO!

D I M E T H Y L S U L F O X I D E (DMSO) AS REACTION SOLVENT Phenomenally high rates for reactions conducted in Dimethyl Sulfoxide are being reported by research chemists. Examples:

C a r b a n i o n f o r m a t i o n : P r o t o n ab­ straction from carbon by bases proceeds up to one billion times faster than in methanol.

D i s p l a c e m e n t r e a c t i o n s between organic halides or sulfonates and anions such as cyanides, azides, thiocyanates, nitrites, alkoxides or malonic ester anion occur 1,000 to 100,000 times faster than in alcohols.

Translocation of double b o n d s : Base catalyzed isomerizations of allyl to propenyl ethers occur 1,400 times faster in DMSO than in dimethoxyethane.

Greater solvent power for m a n y p r o c e s s e s : The ability of DMSO to dissolve both monomers and polymers equips it to handle in situ polymerization. For example, polyacrylonitrile fibers are being spun commer­ cially from a DMSO reaction solution without intermediate isolation of the polymer. The synthesis of sugar esters can be carried out advantageously in DMSO because of its high solubility for each reactant.

Write for DMSO sample and literature on reactions to:

CROWN ZELLERBACH Chemical Products Division CamasB, Washington

Dimethyl Sulfoxide! φ Polymerization medium and spin­ ning solvent for fibers, φ Reaction solvent for sugar ester synthesis. φ Reaction solvent for synthesis of acetylene derivatives. # Solvent for polyurethanes in fabric coating or thread forming. # Solvent for difficultly soluble pest­ icides, p i g m e n t s , dyestuffs a n d polymers. Crown Zellerbach's DMSO is a high purity, water white, polar, organic solvent, boiling at 1 8 9 ° C , melting above 18.2°C. It is hygroscopic, mis­ cible with water in all proportions, and has a low order of toxicity.