Phosgene → 5-Methyl-2-propargyloxyphenylsulfonylisocyanate

Participants

Reaction Steps

A mixture of 22.4 g of 5-methyl-2-propargyloxyphenylsulfonamide, 9.9 g of n-butylisocyanate, 0.3 g of 1,4-diazabicyclo(2,2,2)octane and 350 ml of absolute xylene is refluxed for 30 minutes; and about 20 g of phosgene are subsequently introduced at 115°-120° C. during 2 hours. After the excess of phosgene has been removed from the reaction mixture by feeding in nitrogen, the mixture is cooled to room temperature, filtered, and concentrated in vacuo. There is thus obtained as crude product 28.1 g of 5-methyl-2-propargyloxyphenylsulfonylisocyanate in the form of brown oil. This crude product is used, without further purification, in the subsequent stage.

Provenance & Evidence