Iodine → 2,6-Dichloro-5-fluoro-4-iodonicotinonitrile

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of diisopropylamine (15.9 g, 157 mmol) in THF (400 ml) at −78° C. was added n-butyllithium (2.5 M hexanes, 154 mmol), and the solution was stirred at −78° C. for 30 minutes. The lithium diisopropylamide solution was then added slowly dropwise to a −78° C. solution of 2,6-dichloro-5-fluoronicotinonitrile (10.0 g, 52.3 mmol) and iodine (26.5 g, 104 mmol) in THF (175 ml). Upon completion of the addition, the reaction was allowed to warm slowly to room temperature, and stirred at room temperature for 12 hours. An aqueous 10% Na2S2O3 solution (500 ml) was added and the reaction was extracted with EtOAc (3×300 ml). The combined organic fractions were dried over Na2SO4, filtered, and then concentrated to give the title compound (14.5 g, 87%) as a brown solid that was used without further purification.

Herkunft & Nachweise