Cyclohexanecarboxylic acid → Tert-butyl 3-(3-(cyclohexanecarboxamido)phenyl)propylcarbamate

Participants

Reaction Steps

To a mixture of cyclohexanecarboxylic acid (21) (0.23 ml, 1.79 mmol), TBTU (0.56 g, 1.74 mmol) and iPr2EtN (0.33 ml, 1.89 mmol) in DMF (20 ml) was added tert-butyl 3-(3-(cyclohexylmethylamino)phenyl)propylcarbamate (17) (0.40 g, 1.59 mmol) in DMF (5 ml). The mixture was stirred at room temperature for 18 h and then diluted with water. The solution was extracted with ethyl acetate and the combined extracts were washed with water, aqueous NaHCO3 and brine, dried over Na2SO4 and concentrated under reduced pressure. Purification by flash chromatography (5 to 50% EtOAc-hexanes gradient) gave tert-butyl 3-(3-(cyclohexanecarboxamido)phenyl)propylcarbamate (22) as a colorless oil. Yield (0.455 g, 78%); Yield (0.2 g, 32%); 1H NMR (400 MHz, CDCl3) δ 7.43 (br s, 1H), 7.26-7.28 (m, 2H), 7.20 (t, J=7.6 Hz, 1H), 7.08 (br s, 1H), 6.89-6.91 (m, 1H), 3.12 (t, J=6.0 Hz, 2H), 2.61 (t, J=8.4 Hz, 2H), 2.17-2.23 (m, 1H), 1.93-1.96 (m, 2H), 1.74-1.86 (m, 3H), 1.65-1.72 (m, 2H), 1.48-1.59 (m, 1H), 1.31-1.42 (m, 2H), 1.43 (s, 9H), 1.22-1.38 (m, 4H).

Provenance & Evidence