Methyl Isocyanate → HCID 21399269, compound

Participants

Reaction Steps

A solution of 35.0 g of 5-amino-4-cyano-3-(ethylthio)-isothiazole, 11.9 g of methyl isocyanate, 50 drops of dibutyltin diacetate in 175 ml of dried tetrahydrofuran was heated under reflux during 15 hours. Thin-layer chromatographic analysis of the reaction mixture indicated the reaction was 50% complete. An additional 11 ml of methyl isocyanate and 10-15 drops of dibutyltin diacetate were added. The reaction mixture was heated with stirring for 2 days. Thin-layer chromatographic analysis of the reaction mixture indicated the reaction to be complete. The reaction mixture was cooled, and the solid collected by filtration. The filtrate was evaporated to give a second crop, which was recrystallized from ethanol/dimethylformamide. The total yield of pure 1-methyl-3-(4-cyano-3-(ethylthio)-5-isothiazolyl)urea was 37.6 g; m.p. 246° (phase change) - 263°. The nmr spectrum was consistent with the assigned structure.

Provenance & Evidence