4-Nitrophenol → 4-(4-Nitrophenoxy)piperidine

Participants

Reaction Steps

N-Boc-4-piperidinol (10 g, 50 mmol), 4-nitrophenol (7.0 g, 50 mmol) and triphenylphosphine (15.7 g, 60 mmol) were dissolved in dry tetrahydrofuran (150 mL), and cooled on the ice bath. Diisopropyl azodicarboxylate (11.8 mL, 60 mmol) was added slowly, and stirred for 2 days at room temperature. The solvent was distilled off under reduced pressure, diethyl ether was added, and the solid precipitate was filtered off. The filtrate was concentrated and the product was purified by silica gel column chromatography (hexane/ethyl acetate=6/1). Trifluoroacetic acid was added to the obtained residue and stirred at room temperature for 1 hour. After distillation under reduced pressure, 1N sodium hydroxide aqueous solution was added, and the mixture extracted with ethyl acetate. After drying with anhydrous sodium sulfate, the product was concentrated and dried to obtain the target substance (6.75 g, 61%).

Provenance & Evidence