تفاعل #1857559

معادلة التفاعل

(2S,6S,7S)-2-((tert-butoxycarbonyl)amino)-7-((S)-1-hydroxyethyl)-10-methyl-6-propoxyundecanoic acid

MNBA

→

title compound

المردود 59.2%

tert-butyl ((3S,7S,8S,9S)-8-isopentyl-9-methyl-2-oxo-7-propoxyoxonan-3-yl)carbamate

المردود 59.2%

المذيبات

DCM

DCM

ظروف التفاعل

المعالجة

1. 1
   أخرىat room temperature
2. 2
   workup.ADDITIONthe reaction mixture was treated with Celite® (5 scoopula tip-fulls)
3. 3
   أخرىThe solvent was removed under reduced pressure
4. 4
   أخرىpurified

الإجراء التجريبي

A solution of (2S,6S,7S)-2-((tert-butoxycarbonyl)amino)-7-((S)-1-hydroxyethyl)-10-methyl-6-propoxyundecanoic acid (627 mg, 1.50 mmol) in anhydrous DCM (80 mL) was added over 12 h using a syringe pump to a stirred solution of MNBA (1.03 g, 3.00 mmol) and DMAP (1.10 g, 9.01 mmol) in DCM (150 mL) at room temperature. Stirring was continued for an additional 7 h then the reaction mixture was treated with Celite® (5 scoopula tip-fulls). The solvent was removed under reduced pressure and the resulting adsorbed material was directly loaded onto a column and purified using flash column chromatography (80 g SiO2, 0→30% EtOAc/hexanes) to afford the title compound (355 mg, 0.888 mmol, 59%) as a colorless oil: 1H NMR (400 MHz, CDCl3) δ 5.06 (d, J=8.2 Hz, 1H), 4.70 (dq, J=10.1, 6.4 Hz, 1H), 4.24-4.14 (m, 1H), 3.50 (app dt, J=9.0, 6.4 Hz, 1H), 3.28-3.19 (m, 1H), 3.13 (app dt, J=8.8, 6.6 Hz, 1H), 2.30-2.18 (m, 1H), 2.11 (dddd, J=15.6, 10.1, 7.9, 5.2 Hz, 1H), 1.87 (app dq, J=13.1, 4.6 Hz, 1H), 1.78-1.35 (m, 16H), 1.31 (d, J=6.3 Hz, 3H), 1.24-1.03 (m, 3H), 0.96-0.75 (m, 10H); 13C NMR (101 MHz, CDCl3) δ 173.11, 154.94, 79.93, 79.70, 73.53, 70.41, 52.46, 46.66, 34.41, 33.63, 29.03, 28.75, 28.33, 26.26, 23.30, 22.61, 22.44, 19.26, 17.80, 10.88; ESIMS m/z 422 ([M+Na]+).

المصدر