Synthesis of high specific activity [14CO] methyl isocyanate and its use in the preparation of [14CO] eserine, [14CO] carbaryl and [14CO] IPMU

Article abstract of DOI:10.1002/(SICI)1099-1344(199805)41:5<387::AID-JLCR92>3.0.CO;2-S

The preparation of [¹⁴CO] methyl isocyanate from [1-¹⁴C] acetyl chloride and activated sodium azide through the Curtius rearrangement was optimized (50% yield/[1-¹⁴C] sodium acetate- 50 mCi/mmol) and the reagent immediately used for the synthesis of [¹⁴CO] eserine, [¹⁴CO] carbaryl and [¹⁴CO] IPMU. The condensation of methyl isocyanate with eseroline in the presence of triethylamine does not give rise to eserine but to the isomeric urea derivative 3.