반응 #83122
ord-41ed5fb5f01245898410dd7345481174
반응 방정식
반응 조건
후처리
- 1세척washed with 1M citric acid solution
- 2건조The dried (MgSO4) organic phase
- 3기타was evaporated to dryness
- 4기타chromatographed over silica using 2% MeOH
실험 절차
A solution of the α-methyl-D-tryptophyl-L-phenylalaninol (0.5 g, 1.42 mmol) and 4-N,N-dimethylaminopyridine (0.2 g, 1.64 mmol), in anhydrous THF (20 mL) was treated dropwise with a solution of 2-adamantylchloroformate (1.4 mmol) in anhydrous THF (20 mL) at room temperature. The reaction was monitored by IR spectroscopy. Once complete, the reaction mixture was diluted with ethyl acetate and washed with 1M citric acid solution, then water. The dried (MgSO4) organic phase was evaporated to dryness and chromatographed over silica using 2% MeOH:98% CH2Cl2 as eluant. This gave the required compound (65% along with 20% carbonate impurity. NOTE: Some of the more acid labile urethanes required chromatography on neutral stationary phases. mp 96°-100° C. (EtOAc-hexane); IR (KBr) 3316, 1695 and 1658 cm-1 ; NMR (CD3OD) δ1.28 (3H, s), 1.55 (2H, m), 1.68-2.06 (12H, m), 2.76 (2H, ABx, J 13.5 and 17Hz), 3.31 (2H, Abq, J 14.5Hz), 3.45 (2H, m), 4.12 (1H, m), 4.78 (1H, br.s) and 6.8-7.5 (10H, m); Anal (C32H39N3O4), C, H, N.