Benzyl betulinate → (1R,3aS,5aR,5bR,7aR,11aR,11bR,13aR,13bR)-benzyl 5a,5b,8,8,11a-pentamethyl-9-oxo-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[alpha]chrysene-3a-carboxylate

HRID 338623Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 338623
[OH:1][C@H:2]1[CH2:19][CH2:18][C@@:17]2([CH3:20])[C@@H:4]([CH2:5][CH2:6][C@:7]3([CH3:38])[C@@H:16]2[CH2:15][CH2:14][C@H:13]2[C@@:8]3([CH3:37])[CH2:9][CH2:10][C@@:11]3([C:27]([O:29][CH2:30][C:31]4[CH:36]=[CH:35][CH:34]=[CH:33][CH:32]=4)=[O:28])[CH2:23][CH2:22][C@@H:21]([C:24]([CH3:26])=[CH2:25])[C@@H:12]32)[C:3]1([CH3:40])[CH3:39].C1C=C[NH+]=CC=1.[O-][Cr](Cl)(=O)=O>ClCCl>[CH3:37][C@:8]12[C@@:7]3([CH3:38])[C@@H:16]([C@:17]4([CH3:20])[C@@H:4]([CH2:5][CH2:6]3)[C:3]([CH3:39])([CH3:40])[C:2](=[O:1])[CH2:19][CH2:18]4)[CH2:15][CH2:14][C@@H:13]1[C@H:12]1[C@H:21]([C:24]([CH3:26])=[CH2:25])[CH2:22][CH2:23][C@:11]1([C:27]([O:29][CH2:30][C:31]1[CH:32]=[CH:33][CH:34]=[CH:35][CH:36]=1)=[O:28])[CH2:10][CH2:9]2

Komponenten

4

Edukt 2

HCID 44626706Benzyl betulinateHCID 178418287HCID 178418287, Verbindung

Produkt 1

HCID 60152984(1R,3aS,5aR,5bR,7aR,11aR,11bR,13aR,13bR)-benzyl 5a,5b,8,8,11a-pentamethyl-9-oxo-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[alpha]chrysene-3a-carboxylateAusbeute 98 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 6344DichloromethaneLösungsmittel

Versuchsvorschrift

To a solution of (1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-benzyl 9-hydroxy-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[a]chrysene-3a-carboxylate (7.1 g, 12.98 mmol) in dichloromethane (100 mL) was added PCC (4.20 g, 19.48 mmol). After stirring for five minutes, the mixture turned a deep crimson color. The mixture was further stirred for 5.5 h. The mixture was filtered through a pad of celite and silica gel which was washed with dichloromethane and then with a 1:1 mixture of ethyl acetate:hexanes. The filtrate was concentrated under reduced pressure to give (1R,3aS,5aR,5bR,7aR,11aR,11bR,13aR,13bR)-benzyl 5a,5b,8,8,11a-pentamethyl-9-oxo-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[a]chrysene-3a-carboxylate (6.92 g, 98% yield) as a white foam. 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 7.38-7.28 (m, 5H), 5.17-5.06 (m, 2H), 4.72 (d, J=1.83 Hz, 1H), 4.59 (s, 1H), 3.01 (td, J=10.99, 4.88 Hz, 1H), 2.51-2.43 (m, 1H), 2.42-2.34 (m, 1H), 2.28 (dt, J=12.59, 3.17 Hz, 1H), 2.21 (td, J=12.28, 3.51 Hz, 1H), 1.94-1.82 (m, 3H), 1.67 (s, 3H), 1.05 (s, 3H), 1.01 (s, 3H), 1.73-0.95 (m, 17H), 0.94 (s, 3H), 0.89 (s, 3H), 0.78 (s, 3H).

Aufarbeitung

  1. stirringThe mixture was further stirred for 5.5 h
  2. filtrationThe mixture was filtered through a pad of celite and silica gel which
  3. washwas washed with dichloromethane
  4. additionwith a 1:1 mixture of ethyl acetate
  5. concentrationThe filtrate was concentrated under reduced pressure

Quellen und Nachweise

ORD-Eintrag
ord-e09c7f749d8d47c3aa9bede5e31fa85f
Quelldatensatz
uspto-grants-2014_11
Patentnummer
US08889854B2

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