Nitric Acid → 4-(4-Nitrophenyl)piperidine

Participants

Reaction Conditions

Reaction Steps

4-Phenylpiperidine (8 g, 49 mmol) was dissolved in 40 mL acetic acid and stirred with cooling below 25° C. while adding a solution of 2.64 mL sulphuric acid in 40 mL acetic acid. The solution was stirred at 20° C. while adding a solution of 2.08 mL 99% nitric acid in 20 mL acetic acid. Sulphuric acid (40 mL) was added without cooling, the temperature peaking at 58° C. When the solution had cooled to 25° C. it was added to 100 g ice/water and basified with a total of 150 g sodium hydrogen carbonate at 40° C. The mixture was then brought to pH 14 with 5M-sodium hydroxide solution. The mixture was extracted with dichloromethane (3×150 mL), dried with sodium sulphate and evaporated giving a pale yellow solid. Recrystallisation from a total of 180 mL cyclohexane (hot filtration) gave the product as pale beige solid. NMR δ 8.18(d,2H), 7.40(d,2H), 3.21(m,2H), 2.77(m,3H), 1.82(m,3H), 1.68(m,2H).

Provenance & Evidence