Diisopropylethylamine → 5-Vinylpyrazin-2-amine

Participants

Reaction Conditions

Reaction Steps

A solution of 2-amino-5-bromopyrazine (500 mg, 2.87 mmol) in N,N-dimethylformamide (15 mL) was treated with tetrakis(triphenylphosphine)palladium(0) (66 mg, 0.06 mmol), N,N-diisopropylethylamine (1.25 mL, 7.18 mmol), lithium chloride (426 mg, 0.06 mmol), and vinyltri-n-butyltin (840 μL, 2.87 mmol), and the reaction was heated at 120° C. for 4 h. After such time, the reaction was cooled to 25° C., treated with a saturated aqueous potassium fluoride solution (10 mL), and stirred at 25° C. overnight for 16 h. The solution was then diluted with methylene chloride (25 mL) and extracted with methylene chloride (3×15 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 2/3 to 1/4 hexanes/ethyl acetate) afforded 2-amino-5-vinylpyrazine (211 mg, 61%) as a light yellow solid: EI-HRMS m/e calcd for C6H7N3 (M+) 121.0640, found 121.0642.

Provenance & Evidence