Iodine → tert-Butyl (4-chloro-3-iodopyridin-2-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl (4-chloropyridin-2-yl)carbamate (10 g, 43.7 mmol) and tetramethylethylenediamine (12 mL) in tetrahydrofuran (200 mL) at −70° C. was added 2.5M n-butyl lithium in hexane (52 mL, 131 mmol) over 30 minutes. The mixture was stirred at −70° C. for 1 hour and treated with a solution of iodine (27 g, 109 mmol) in 100 mL tetrahydrofuran at −70° C. The mixture was stirred at −70° C. for 30 minutes and warmed to room temperature. Saturated aqueous sodium hydrogen sulfite (200 mL) was added and the mixture stirred for 30 minutes. The mixture was extracted with ethyl acetate and the organic layers were washed with water and brine, dried over sodium sulfate, filtered, concentrated and precipitated from ethyl acetate/hexane to afford the title compound. LCMS: 298.9 (M+H—NCOOH)+.

Provenance & Evidence