Sulfuric Acid → 4-(Phenylamino)-1-(phenylmethyl)-4-piperidinecarboxamide

Participants

Reaction Conditions

Reaction Steps

Aminonitrile 1 (2.0 g, 6.86 mmol) was dissolved in 11 mL of trifluoroacetic acid under a nitrogen atmosphere. Sulfuric acid (2.7 mL) was added dropwise. The light brown solution was stirred at 45-50° C. for 16 h. The reaction mixture was cooled to room temperature and slowly poured into an ammonium hydroxide 40 mL/ice mixture. The solution was filtered and the solids were collected to give 1.73 g of amide 2 in an 82% yield. mp 179-182° C.; 1H NMR (CDCl3) δ 7.33-7.16 (m, 5H), 6.89 (br s, 1H), 6.78 (t, 1H, J=7.33 Hz), 6.63 (d, 2H, J=7.33 Hz), 5.48 (s, 1H), 4.05 (s, 1H), 2.77-2.71 (m, 2H), 2.37-2.30 (m, 2H), 2.10 (t, 2H, J=11.91 Hz), 1.95 (br d, 2H, J=13.28 Hz); 13C NMR (CDCl3) 178.7, 143.8, 138.3, 129.3, 129.1, 129.0, 128.3, 127.2, 119.3, 116.2, 63.1, 58.3, 48.8, 31.4.

Provenance & Evidence