Ammonium Chloride → 6-Chloropyridine-3-carboximidamide

Participants

Reaction Conditions

Reaction Steps

Suspend ammonium chloride (1.16 g, 21.6 mmol) in toluene (10 mL). Cool to 0° C. and slowly add 2.0 M Al(CH3)3 in toluene (10.8 mL, 21.6 mmol) (see Tetrahedron Lett. 1990, 31(14), 1969-1972). After the gas stops evolving, add a solution of 6-chloronicotinonitrile (1.00 g, 7.22 mmol) in toluene (52 mL). Heat to 80° C. overnight. Cool the reaction mixture, then slowly pour into slurry of silica gel (40 g) in CHCl3 (200 mL). Stir for 10 minutes before filtering. Filter and wash the silica plug with methanol (2× 100 mL). Concentrate the filtrate and purify by 10 g SCX column washing with methanol and then eluting with 2.0 M NH3 in methanol to give the title compound (0.458 g, 40.8%): MS ES+ 155.9 (M+H)+: HPLC [YMC-Pack Pro C-18 (150×4.6 mm, S-5 microm), acetonitrile in water containing 0.01% concentrated HCl at 1.0 mL/min, 30-99% over 19 min], tR=1.2 min, 97.2% purity.

Provenance & Evidence