Reaktion #43556

Reaktionsgleichung

morpholine

3-(R)-(4-(S)-Benzyl-2-oxo-oxazolidine-3-carbonyl)-5-cyclohexyl-pentanoic acid

HATU

morpholine

DIPEA

→

1-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-2-(R)-(2-cyclohexyl-ethyl)-4-morpholin-4-yl-butane-1,4-dione

Ausbeute 92.3%

Lösungsmittel

CH2Cl2

ethyl acetate

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted with 0.5 M HCl (2×10 mL), saturated NaHCO3, and brine
2. 2
   TrocknenThe organic layer is dried over MgSO4
3. 3
   Filtrationfiltered
4. 4
   Sonstigeevaporated
5. 5
   Sonstigepurified by normal-phase silica chromatography in a 20-50% ethyl acetate in hexanes gradient

Vorschrift

3-(R)-(4-(S)-Benzyl-2-oxo-oxazolidine-3-carbonyl)-5-cyclohexyl-pentanoic acid (1.76 g, 4.53 mmol, 1.0 eq.) dissolved in DMF (10 mL) and treated with HATU (1.3 g, 5.0 mmol, 1.1 eq.), morpholine (680 μL, 7.77 mmol, 1.7 eq.) and DIPEA (870 μL, 5.0 mmol, 1.1 eq.). Alternatively an additional equivalent of morpholine can be used in the reaction and CH2Cl2 can be used as the reaction solvent. The reaction is monitored by LC/MS. The reaction mixture is diluted with ethyl acetate (50 mL) and extracted with 0.5 M HCl (2×10 mL), saturated NaHCO3, and brine. The organic layer is dried over MgSO4, filtered and evaporated. The crude mixture is used in Step F directly or purified by normal-phase silica chromatography in a 20-50% ethyl acetate in hexanes gradient to provide 1-(4-(S)-Benzyl-2-oxo-oxazolidin-3-yl)-2-(R)-(2-cyclohexyl-ethyl)-4-morpholin-4-yl-butane-1,4-dione as a white solid (1.91 g, 4.18 mmol, 92%): 1H NMR (CDCl3, 400 MHz) δ 0.80-0.91 (m, 2H), 1.09-1.27 (m, 6H), 1.44-1.53 (m, 1H), 1.61-1.73 (m, 6H), 2.12 (s, 2H), 2.35 (dd, 1H, J=17.2, 4.0 Hz), 2.49 (dd, 1H, J=13.6, 9.6 Hz), 2.71 (dd, 1H, J=17.6, 10.8 Hz), 3.03 (dd, 1H, J=13.6, 3.2 Hz), 3.48-3.72 (m, 8H), 3.87-3.97 (m, 3H), 4.43 (m, 1H), 6.90-7.10 (m, 5H), 8.02 (s, 1H).

Quelle