Oxalyl chloride → methyl 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(chlorocarbonyl)-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
Reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:10]=[CH:9][C:8]([C:11]2[C:12]([CH3:42])([CH3:41])[C@H:13]3[C@:26]([CH3:29])([CH2:27][CH:28]=2)[C@@H:25]2[C@:16]([CH3:40])([C@@:17]4([CH3:39])[CH:22]([CH2:23][CH2:24]2)[C@H:21]2[C@H:30]([C:33]([CH3:35])=[CH2:34])[CH2:31][CH2:32][C@:20]2([C:36]([OH:38])=O)[CH2:19][CH2:18]4)[CH2:15][CH2:14]3)=[CH:7][CH:6]=1)=[O:4].C(Cl)(=O)C([Cl:46])=O>ClCCl>[Cl:46][C:36]([C@:20]12[CH2:32][CH2:31][C@@H:30]([C:33]([CH3:35])=[CH2:34])[C@@H:21]1[C@@H:22]1[C@@:17]([CH3:39])([CH2:18][CH2:19]2)[C@@:16]2([CH3:40])[C@@H:25]([C@:26]3([CH3:29])[C@@H:13]([CH2:14][CH2:15]2)[C:12]([CH3:41])([CH3:42])[C:11]([C:8]2[CH:9]=[CH:10][C:5]([C:3]([O:2][CH3:1])=[O:4])=[CH:6][CH:7]=2)=[CH:28][CH2:27]3)[CH2:24][CH2:23]1)=[O:38]Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a flask containing (1R,3aS,5aR,5bR,7aR,11aS,11bR,13bR)-9-(4-(methoxycarbonyl)phenyl)-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]chrysene-3a-carboxylic acid (0.1-4.2 mmol scale) was added oxalyl chloride (2M in dichloromethane) (10-50 equiv.). The solution was stirred at rt for 2-5 h and was stripped of solvent. The residue was dissolved in dichloromethane and concentrated two additional times, then was used with no additional purification in the next step. 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 7.92 (d, J=8.55 Hz, 2H), 7.19 (d, J=8.24 Hz, 2H), 5.26-5.30 (m, 1H), 4.73 (d, J=1.53 Hz, 1H), 4.62-4.64 (m, 1H), 3.90 (s, 3H), 2.81 (td, J=11.14, 4.58 Hz, 1H), 2.47 (ddd, J=13.58, 3.20, 3.05 Hz, 1H), 2.19-2.28 (m, 2H), 2.10 (dd, J=17.09, 6.41 Hz, 1H), 1.85-1.99 (m, 1H), 1.68 (s, 3H), 1.00 (s, 6H), 0.98 (s, 3H), 0.92 (s, 3H), 0.92 (s, 3H), 0.84-1.83 (m, 17H). 13C NMR (126 MHz, CHLOROFORM-d) δ ppm 177.49, 167.35, 149.46, 148.81, 146.39, 130.17 (s, 2C), 128.61 (s, 2C), 128.03, 124.12, 110.40, 68.00, 52.99, 52.11, 49.78, 49.67, 46.11, 42.54, 41.86, 40.70, 38.00, 37.60, 36.39, 36.31, 33.64, 32.3, 29.98, 29.72, 29.54, 25.60, 21.37, 21.13, 19.86, 19.48, 16.59, 15.71, 14.89.
Workup
- concentrationconcentrated two additional times
- customwas used with no additional purification in the next step
Sources & evidence
- ORD record
- ord-fdf8690e4db040deb6502f4d3c9f6958
- Source dataset
- uspto-grants-2014_08
- Patent number
- US08802661B2
Reaction notes
Loading…