Iodine → Tert-butyl 4-iodo-6-phenylpyridin-3-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

A solution of (6-phenylpyridin-3-yl)carbamic acid tert-butyl ester (5.54 g, 20.5 mmol) and TMEDA (6.49 mL, 43.0 mmol) in 100 mL of anhydrous diethyl ether was treated with n-BuLi at −78° C. After 15 minutes at −78° C., the mixture was warmed to −10° C. and stirred for an additional 3 hours. The reaction mixture was then cooled to −78° C. and a solution of iodine in a mixture of 10 mL of THF and 100 mL of diethyl ether was added dropwise. After 2 hours at −78° C., the mixture was allowed to warm to 0° C. and was quenched with 400 mL of saturated aqueous ammonium chloride solution. The organic layer was washed with five 100 mL portions of saturated aqueous sodium thiosulfate. The combined aqueous layers extracted with three 200 mL portions of ethyl acetate. The combined organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo. Chromatography on SiO2 (0% to 70% ethyl acetate in hexanes, gradient) afforded 900 mg of the title product as yellow oil that solidified over time (11% yield).

Provenance & Evidence