2-Amino-5-chloropyridine → 5-Chloro-2-isothiocyanatopyridine

Participants

Reaction Steps

2-Amino-5-chloropyridine (10.28 g) was added in portions, with stirring, over a period of 25 minutes to a solution of thiocarbonyl diimidazole (14.26 g) in acetonitrile (100 ml) at ambient temperature. The stirring was continued and the solution/suspension was left at ambient temperature for a few hours. The precipitate was filtered and washed with acetonitrile (3×25 ml). The solid residue was dissolved in hot acetone and filtered. The acetone solution was evaporated in vacuo, the residue was dissolved in hot ethyl acetate and filtered through a pad of silica (diam. 7 cm×3 cm). The silica was washed with another portion of hot ethyl acetate. The combined solutions were evaporated in vacuo to yield a crude product (5 g) of the titled product.

Provenance & Evidence