PRACTICAL AND SAFE SULFONYLATION OF 2-ALKYNYL AND 2-ALKENYL ALCOHOLS USING THE COMBINED BASES OF A CATALYTIC AMOUNT OF TERTIARY AMINE AND POTASSIUM CARBONATE

Several 2-alkynyl and 2-alkenyl alcohols were effectively sulfonylated with methanesulfonyl chloride or p-toluenesulfonyl chloride using the combined bases of a catalytic amount of tertiary amine and potassium carbonate. The reaction was conducted with reliable safety and while a voiding the disposal of wasted amines. The mesylation of 2-propyn-1-ol proceeded on a large scale (more than 20 kg) without a substantial pr oduction of explosive 3-chloro-1-propyne. The choice of the catalysts was important, and sterically unhindered tertiary amines, such as trim ethylamine, N,N-dimethylbenzylamine, and triethylamine, were effective . Without these catalysts the reactions were significantly retarded. T he reaction was so mild that it could be applied to complex and optica lly active droxy-3-methyl-2-(2-propynyl)-2-cyclopenten-1-one, which is an important alcohol moiety of synthetic pyrethroids.