Sodium Bicarbonate → 5-(Methylthio)pyrazin-2-amine

Participants

Reaction Conditions

Reaction Steps

A mixture of tetrakis(triphenylphosphine)palladium(0) (3.32 g, 2.87 mmol) and 2-amino-5-bromopyrazine (5.00 g, 28.73 mmol) in N,N-dimethylformamide (144 mL) was treated with 95% sodium thiomethoxide (4.24 g, 57.47 mmol). The resulting reaction mixture was heated at 60° C. for 10 h. The reaction mixture was allowed to cool to 25° C. and then was poured into a saturated aqueous sodium bicarbonate solution (500 mL). The product was extracted with ethyl acetate (5×200 mL). The combined organic layers were washed with a saturated aqueous sodium chloride solution (1×200 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230–400 mesh, 3/7 ethyl acetate/hexanes) afforded 5-methylsulfanyl-pyrazin-2-ylamine (1.66 g, 40.9%) as an orange solid: mp 65–67° C.; EI-HRMS m/e calcd for C5H7N3S (M+) 141.0361, found 141.0357.

Provenance & Evidence