Hydrochloric Acid → (5-(Pyridin-3-ylcarbamoyl)pentyl]carbamic acid tert-butyl ester

Participants

Reaction Steps

To a mixture of 3-aminopyridine (1, 2.82 g, 30 mmole) and 6-tert-Butoxycarbonylamino-hexanoic acid (2, 9.2 g, 40 mmole) in methylene chloride (50 mL) was added HOBt (135 mg, 1 mmole), EDC. HCl (7.6 g, 40 mmole) followed by DIPEA (10.45 mL, 60 mmole). The reaction mixture was stirred at room temperature for 3 h. At this point the TLC showed the disappearance of starting material. The reaction solution was washed with water (3×25 mL), followed by aqueous sodium bicarbonate (25 mL), then brine and finally dried over anhydrous sodium sulfate, filtered and concentrated. The crude residue was purified by column chromatography using 1% methanol in methylene chloride as the eluant to give the pure product as an oily residue. This residue on trituration with hexane gave 3 as a colorless solid (6.3 g, 68%, mp 96-98° C.). 1H NMR (CDCl3) δ 8.68 (br s, 2H), 8.48 (m, 1H), 8.30 (m, 2H), 7.32 (m, 1H), 4.62 (br s, 1H), 3.16 (m, 2H), 2.40 (m, 2H), 2.78 (m, 2H), 1.50 (m, 4H), 1.40 (s, 9H).

Provenance & Evidence