HCID 86676398, compound → tert-butyl 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-formyl-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate

HRID 405052Notes

Reaction equation

HRID 405052 reaction equation
[OH:1][CH2:2][C@:3]12[CH2:41][CH2:40][C@@H:39]([C:42]([CH3:44])=[CH2:43])[C@@H:4]1[C@@H:5]1[C@@:18]([CH3:21])([CH2:19][CH2:20]2)[C@@:17]2([CH3:22])[C@@H:8]([C@:9]3([CH3:38])[C@@H:14]([CH2:15][CH2:16]2)[C:13]([CH3:24])([CH3:23])[C:12]([C:25]2[CH:37]=[CH:36][C:28]([C:29]([O:31][C:32]([CH3:35])([CH3:34])[CH3:33])=[O:30])=[CH:27][CH:26]=2)=[CH:11][CH2:10]3)[CH2:7][CH2:6]1.C1C=C[NH+]=CC=1.[O-][Cr](Cl)(=O)=O>ClCCl>[CH:2]([C@:3]12[CH2:41][CH2:40][C@@H:39]([C:42]([CH3:44])=[CH2:43])[C@@H:4]1[C@@H:5]1[C@@:18]([CH3:21])([CH2:19][CH2:20]2)[C@@:17]2([CH3:22])[C@@H:8]([C@:9]3([CH3:38])[C@@H:14]([CH2:15][CH2:16]2)[C:13]([CH3:23])([CH3:24])[C:12]([C:25]2[CH:26]=[CH:27][C:28]([C:29]([O:31][C:32]([CH3:33])([CH3:34])[CH3:35])=[O:30])=[CH:36][CH:37]=2)=[CH:11][CH2:10]3)[CH2:7][CH2:6]1)=[O:1]

Participants

4

Reactant 2

HCID 86676398HCID 86676398, compoundHCID 178418287HCID 178418287, compound

Product 1

HCID 86676397tert-butyl 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-formyl-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoateYield 80.5%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a solution of tert-butyl 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(hydroxymethyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate (5.6 g, 9.32 mmol) in dichloromethane (100 ml) was added PCC (3.01 g, 13.98 mmol). The mixture was stirred at rt for 6.5 h then was filtered through a pad of celite and silica gel which was washed with dichloromethane then 1:1 ethyl acetate:hexanes. The filtrate was concentrated under reduced pressure and the residue was purified by flash chromatography using a 0-10% EtOAc in hexanes gradient to afford the title compound as a white solid (4.49 g, 7.50 mmol, 80% yield). 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 9.68 (1H, d, J=1.5 Hz), 7.87 (2H, d, J=8.2 Hz), 7.16 (2H, d, J=8.2 Hz), 5.26 (1H, dd, J=6.4, 1.8 Hz), 4.76 (1H, d, J=1.8 Hz), 4.63 (1H, s), 2.88 (1H, td, J=11.1, 5.8 Hz), 2.02-2.15 (3H, m), 1.70 (3H, s), 1.58 (9H, s), 1.00 (3H, s), 0.97 (3H, s), 0.97 (3H, s), 0.91 (6H, s), 0.83-1.94 (19H, m).

Workup

  1. filtrationthen was filtered through a pad of celite and silica gel which
  2. washwas washed with dichloromethane
  3. concentrationThe filtrate was concentrated under reduced pressure
  4. customthe residue was purified by flash chromatography

Sources & evidence

ORD record
ord-bfe714046c704d00817f5eeec5a7b2ae
Source dataset
uspto-grants-2014_06
Patent number
US08748415B2

Reaction notes

Loading…