Triphenylphosphine → 4-[6-(2-Ethoxy-phenyl)-pyrimidin-4-ylcarbamoyl]-piperidine-1-carboxylic acid benzyl ester

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture of 4-(6-chloro-pyrimidin-4-ylcarbamoyl)-piperidine-1-carboxylic acid benzyl ester (VIII) (6.15 g, 16.4 mmol), 2-ethoxyphenylboronic acid (II) (3.00 g, 18.1 mmol) in saturated sodium carbonate solution (10 ml) and 1,4-dioxane (10 ml) was added palladium(II) acetate (0.81 g, 3.6 mmol) followed by triphenylphosphine (0.94 g, 3.6 mmol) at room temperature under an atmosphere of nitrogen. The resulting reaction mixture was heated to reflux at 110° C. for one hour and monitored by TLC. The reaction mixture was filtered through a celite bed and the filtrate was extracted with ethyl acetate (3×100 ml). The organic layers were separated, combined, dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by flash column chromatography (silica gel, elution with 50% ethyl acetate/n-hexanes) to afford 4-[6-(2-ethoxy-phenyl)-pyrimidin-4-ylcarbamoyl]-piperidine-1-carboxylic acid benzyl ester (IX) (3.8 g, 50%) as a pale yellow oil.

Provenance & Evidence