Chlorosulfonyl isocyanate → HCID 86741565, compound

Participants

Reaction Conditions

Reaction Steps

(S)-3-[[(Phenylmethoxy)carbonyl]amino]-2-azetidinone (4.4 g) was suspended in 150 ml of dry ethyl acetate. The mixture was cooled to -50° C. and 3.3 g of chlorosulfonyl isocyanate was added with stirring; stirring was continued without cooling until the temperature reached 0° C. N-(Trimethylsilyl)chloroacetamide (6.0 g) was added and the solution was stirred overnight. The insoluble material was filtered off and the filtrate washed with water. The organic layer was extracted twice with saturated aqueous sodium bicarbonate. The alkaline aqueous layer was acidified to pH 1 with 20% hydrochloric acid and extracted twice with 150 ml portions of ethyl acetate. The organic layers were combined, dried and evaporated to dryness. The oily residue was dissolved in 50 ml of acetone and the pH was adjusted to 6.5 by addition of lN potassium hydroxide. The solvent was removed in vacuo and the crystalline residue filtered with ether, yielding 3.9 g of the title compound.

Provenance & Evidence