Hydrochloric Acid → p-Toluenesulfonic acid

Participants

Reaction Conditions

Reaction Steps

First, 8.6 g of (R) allethrolone and then 16 ml of triethylamine were added at -40° C to 50 ml of methylene chloride and a solution of 21.4 g of p-toluene sulfonyl chloride in 150 ml of methylene chloride was added thereto over 15 minutes at -40° C. The mixture was stirred for 48 hours at -17° C and was then poured into an aqueous iced 0.1N hydrochloric acid solution. The mixture was stirred and the aqueous phase was extracted with ether. The ether extracts were washed with water and dried over magnesium sulfate to obtain 18.5 g of raw product. The latter was chromatographed over silica gel and was eluted with a 9-1 benzene-ethyl acetate mixture to obtain 3.7 g of p-toluene sulfonate of (R) allethrolone.

Provenance & Evidence