反应详情

PyBOP (1.946 g, 3.74 mmol) was added to a solution of [1-(tert-Butoxycarbonyl)azetidin-3-yl]acetic acid (0.805 g, 3.74 mmol) in DMF (10 mL). The mixture was stirred in an ice-bath, ammonia gas was bubbled in for 3 mins and then the mixture was stirred at rt overnight. The reaction mixture was concentrated, water (15 mL) and saturated, aqueous NaHCO3 (5 mL) were added, and the mixture was extracted with EtOAc (20 mL×3). The extracts were combined, washed with water (20 mL) and brine (10mL), dried (Na2SO4) and evaporated. Column chromatography of the residue (ISOLUTE SI, 50 g/150 ml), eluting with EtOAc and heptane (50:50), then EtOAc and then MeOH and EtOAc (1:99, 2:98 and 5:95), gave the title compound (0.461 g, 57.5%) as a white solid. 1H NMR (400 MHz, CDCl3): 1.42 (s, 9H), 2.53 (d, 2H), 2.85-2.96 (m, 1H), 3.60 (dd, 2H), 4.09 (t, 2H), 5.78 (s, br, 2H); 13C NMR (100 MHz, CDCl3): 25.4, 28.3, 39.7, 54.3 (br), 79.4, 156.3, 173.2.

1. customammonia gas was bubbled in for 3 mins
2. stirringthe mixture was stirred at rt overnight
3. concentrationThe reaction mixture was concentrated
4. additionwater (15 mL) and saturated, aqueous NaHCO3 (5 mL) were added
5. extractionthe mixture was extracted with EtOAc (20 mL×3)
6. washwashed with water (20 mL) and brine (10mL)
7. dry with materialdried (Na2SO4)
8. customevaporated
9. washColumn chromatography of the residue (ISOLUTE SI, 50 g/150 ml), eluting with EtOAc and heptane (50:50)