2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → 2-Chloro-4-(pyridin-2-yl)pyrimidine

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-chloropyrimidine (8.0 g, 50 mmol) in THF (100 mL) at −78° C., n-BuLi (24 mL, 60 mmol) was added dropwise under N2. After addition, the reaction solution was stirred for 30 min, a solution of 2-bromopyridine (5.75 g, 50 mmol) in THF (50 mL) was added in portions. The reaction mixture was stirred at −30° C. for 30 min and at 0° C. for 45 min., then quenched with AcOH (5 mL) and water (1 mL). A solution of DDQ (16.3 g, 80 mmol) in THF (50 mL) was added in portions and the mixture was stirred at room temperature for 45 min. TLC (petroleum:EtOAc=5:1) indicated the reaction was complete. The reaction mixture was cooled to 0° C. and 3N NaOH (142 mL) was added and stirred for 30 min. The aqueous layer was extracted with EtOAc (50 mL×3). The combined extract was dried over Na2SO4, concentrated and purified by chromatography, eluted with petroleum ether:EtOAc (10:1 to 5:1) to give title compound (4.8 g, 50%) as a light yellow solid.

Provenance & Evidence