Ammonium Chloride → 1-(3-Benzylpyrido[2,3-b]pyrazin-6-yl]-3-ethylurea

Participants

Reaction Conditions

Reaction Steps

2.4 ml of a 0.5 M solution of benzylzinc bromide (1.20 mmol) in THF and 24.7 mg of tetrakis(triphenylphosphine)palladium(0) (0.02 mmol) were initially charged in 1 ml of dioxane under nitrogen. Subsequently, 102.4 mg of 1-(3-chloropyrido[2,3-b]pyrazin-6-yl)-3-ethylurea (0.41 mmol) and 1 ml of dioxane were added in portions. The mixture was then heated to 100° C. After 7 h, the reaction mixture was allowed to cool and then saturated ammonium chloride solution was added. The aqueous phase was extracted repeatedly with dichloromethane and the collected organic phases were washed with saturated sodium chloride solution, dried over sodium sulphate and freed from the solvent under reduced pressure. Column chromatography purification on silica gel (dichloromethane/methanol eluent) afforded a yellow solid.

Provenance & Evidence