Sulfuric Acid → 4-(4-Butylpiperidin-1-yl)-1-(2-methylphenyl)butan-1-one

Participants

Reaction Steps

In a 25 mL oven-dried flask was charged Mg turnings (125 mg, 5.2 mmol) which were activated by the use of a heat-gun. Under inert atmosphere was added a suspension of 2-iodoanisole (1.13 g, 5.2 mmol) in Et2O (4 mL) and the reaction mixture was allowed to stand at rt for 1 hour. Compound 4 (720 mg, 3.4 mmol) dissolved in Et2O (4 mL) was added and the mixture was refluxed over-night. THF (15 mL) and sulfuric acid (4 mL, 2 M) was added and the reaction mixture was stirred for 4 h, followed by addition of NaOH (6 mL, 2 M). The reaction mixture was extracted with ethyl acetate (3×50 mL), and the combined organic phases were evaporated to dryness to produce 1.2 g of crude 5. The crude product was subjected to CC [eluent: CH2Cl2:CH3OH (99:1)] to give pure 5 (0.42 g, 26%). 1H NMR (CDCl3) δ0.83 (t, 3H), 1.20-1.42 (m, 9H), 1.65-1.73 (d, 2H), 1.96-2.20 (m, 4H), 2.53 (t, 2H), 3.02-3.17 (m, 4H), 3.89 (s, 3H), 6.95-7.01 (m, 2H), 7.44 (t, 1H), 7.65 (d, 1H).

Provenance & Evidence