Isoamyl Nitrite → sodium (Z)-N-oxidobenzenecarboximidoyl cyanide

Phenylacetonitrile (9.72 g, 82.97 mmol) was metered into a suspension of 3.31 g (82.97 mmol) of NaOH in 60 ml of ethanol. Following the complete addition, 11.66 g (99.56 mmol) of isopentyl nitrite were metered in dropwise at temperatures of 15° C. The mixture was then stirred for a further 2 hours at this temperature. The reaction mixture was diluted with 300 ml of diethyl ether, and the precipitated solid was filtered off and washed twice with in each case 50 ml of diethyl ether. The white salt sodium {[(Z)-cyano(phenyl)methylene]amino}oxidanide (7.89 g, 56% yield) can be dried in vacuo or be further used directly. 1.49 g (6.24 mmol) of but-3-yn-1-yl[6-(chloromethyl)pyridin-2-yl]carbamate and 103 mg (0.624 mmol) of potassium iodide were added to a solution of 1.05 g (6.24 mmol) of sodium {[(Z)-cyano(phenyl)methylene]amino}oxidanide in 25 ml of acetonitrile and 10 ml of DMF. The reaction mixture was stirred for 7 h at room temperature, the solvent was removed in vacuo and the residue was dissolved in 100 ml of ethyl acetate. The organic phase was washed with water and dried over MgSO4. After removing the solvent, 2.21 g (99% yield, only 1 oxime isomer) of but-3-yn-1-yl{6-[({[(Z)-cyano(phenyl)methylene]-amino}oxy)methyl]pyridin-2-yl}carbamate were isolated as a colourless solid.