38% |
With dmap; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine; In dichloromethane;Sealed tube; Inert atmosphere; |
To a 50 mL roundbottom flask containing a stir bar was added 1- ((benzyloxy)carbonyl) (L')-r peri di ne-2-carboy 1 i c acid (0.523 g, 1.98 mmol), followed by DCM (20 mL). To the reaction vessel was added (in the order listed) EDCI (0.45 g, 2.5 mmol), TEA (0.696 mL, 0.505 g, 5.0 mmol), and DMAP (0.060 g, 0.50 mmol). The reaction vessel was sealed and flushed with nitrogen. Stirring commenced and 3 -phenyl- 1 -propanol was added via syringe (0.258 mL, 0.258 g, 1.9 mmol). The reaction was allowed to proceed overnight. The following day, the reaction was transferred to a separatory funnel in which it was washed with water (10 mL), dilute HC1 (10 mL 0.5 M HC1), saturated aqueous sodium bicarbonate (20 mL) and brine. The crude product was dried over sodium sulfate and concentrated to dryness in vacuo. The crude product was purified by silica gel (0439) chromatography (1 :4 ethyl acetate: hexanes, R/= 0.30) to yield the pure product as a clear oil (0.276 g, 38 %). NMR (500 MHz) (CDCb) (amide rotamers) d: 7.35 - 7.13 (10H, m), 5.16 - 5.13 (2H, m), 4.97 - 4.85 (1H, m), 4.15 - 4.05 (3H, m), 3.10 - 2.94 (1H, m), 2.68 - 2.61 (2H, m), 2.27 - 2.19 (1H, m), 1.98 - 1.89 (2H, m), 1.71 - 1.62 (3H, m), 1.47 - 1.41 (1H, m), 1.29 - 1.21 (1H, m). 13C NMR (125 MHz) (CDCb) (amide rotamers) d: 171.6, 156.5, 155.4, 141.0, 136.6, 128.4, 128.4, 127.9, 127.8, 126.0, 67.3, 67.2, 64.3, 54.6, 54.4, 41.9, 41.8, 32.0, 26.8, 26.7, 24.7, 24.5, 20.7, 20.6. HRMS calc?d for [M+H] = 382.2018, observed = 382.2044. IR (NaCl, DCM): 3028, 2943, 2860, 1737, 1710, 1454, 1417, 1336, 1255, 1255, 1203, 1163, 1090, 1044. |