반응 #1857561

반응 방정식

tert-butyl ((3S,7S,8R,9S)-8-butyl-7-hydroxy-9-methyl-2-oxooxonan-3-yl)carbamate

isobutyryl chloride

isobutyryl chloride

→

title compound

수율 56.2%

(2S,3S,4S,8S)-8-((tert-butoxycarbonyl)amino)-3-butyl-2-methyl-9-oxooxonan-4-yl isobutyrate

수율 56.2%

용매

pyridine

반응 조건

후처리

1. 1
   workup.ADDITIONwas added
2. 2
   온도cooled to room temperature
3. 3
   기타quenched with sat. aq. NH4Cl (5 ml)
4. 4
   추출extracted with EtOAc (3×10 ml)
5. 5
   건조The combined organic extracts were dried over MgSO4
6. 6
   여과filtered
7. 7
   농축concentrated to dryness
8. 8
   기타The crude residue was purified by flash chromatography (SiO2; EtOAc/hexanes)

실험 절차

To a solution of tert-butyl ((3S,7S,8R,9S)-8-butyl-7-hydroxy-9-methyl-2-oxooxonan-3-yl)carbamate (0.405 g, 1.179 mmol) in pyridine (3.4 mL) was added DMAP (0.029 g, 0.236 mmol) followed by the slow addition of isobutyryl chloride (0.247 ml, 2.36 mmol) at room temperature. The reaction was warmed to 50° C. and stirred for 3 h, at which point additional isobutyryl chloride (0.247 ml, 2.36 mmol) was added. The reaction was stirred at 50° C. for an additional 14 h, cooled to room temperature, quenched with sat. aq. NH4Cl (5 ml), and extracted with EtOAc (3×10 ml). The combined organic extracts were dried over MgSO4, filtered, and concentrated to dryness. The crude residue was purified by flash chromatography (SiO2; EtOAc/hexanes) to give the title compound (0.274 g, 0.663 mmol, 56%) as a colorless oil: 1H NMR (400 MHz, CDCl3) δ 5.15 (d, J=8.3 Hz, 1H), 4.91-4.84 (m, 1H), 4.79 (dq, J=10.0, 6.3 Hz, 1H), 4.27-4.16 (m, 1H), 2.60-2.44 (m, 1H), 2.23 (dt, J=13.8, 7.1 Hz, 1H), 2.15-1.99 (m, 3H), 1.73 (tdd, J=13.0, 7.3, 2.3 Hz, 1H), 1.57-1.46 (m, 1H), 1.44 (s, 9H), 1.34 (d, J=6.4 Hz, 4H), 1.33-1.19 (m, 5H), 1.18-1.12 (m, 6H), 1.04-0.94 (m, 1H), 0.87 (t, J=7.0 Hz, 3H); 13C NMR (101 MHz, CDCl3) δ 175.41, 172.91, 154.98, 79.76, 74.44, 73.12, 52.42, 45.44, 34.24, 33.73, 33.32, 30.88, 28.29, 27.38, 23.25, 19.19, 19.03, 18.88, 18.79, 18.02, 13.82; ESIMS m/z 436 ([M+Na]+).

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