Hydrochloric Acid → 3beta-tert-Butyldimethylsilyloxy-4,4-dimethyl-5alpha-chola-8,14-dien-24 oic acid-N-methoxy-N-methyl amide

HRID 1816482Notes

Reaction equation

[Si:1]([O:8][C@H:9]1[CH2:32][CH2:31][C@@:30]2([CH3:33])[C@@H:11]([CH2:12][CH2:13][C:14]3[C:15]4[C@:26]([CH3:34])([CH2:27][CH2:28][C:29]=32)[C@@H:18]([C@H:19]([CH3:25])[CH2:20][CH2:21][C:22]([OH:24])=O)[CH2:17][CH:16]=4)[C:10]1([CH3:36])[CH3:35])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].C[N:38]1[CH2:43]COCC1.[CH2:44]([O:48]C(Cl)=O)C(C)C.Cl>ClCCl>[CH3:44][O:48][N:38]([CH3:43])[C:22](=[O:24])[CH2:21][CH2:20][C@H:19]([C@@H:18]1[C@:26]2([CH3:34])[C:15]([C:14]3[CH2:13][CH2:12][C@@H:11]4[C@:30]([C:29]=3[CH2:28][CH2:27]2)([CH3:33])[CH2:31][CH2:32][C@H:9]([O:8][Si:1]([C:4]([CH3:6])([CH3:7])[CH3:5])([CH3:3])[CH3:2])[C:10]4([CH3:36])[CH3:35])=[CH:16][CH2:17]1)[CH3:25]

Participants

Conditions

Temperature: -15 °C

Procedure

3β-tert-Butyldimethylsilyloxy-4,4-dimethyl-5α-chola-8,14-dien-24-oic acid (5.0 g) is dissolved in 250 ml of dry dichloromethane. After cooling to −15° C., 2.14 ml of N-methylmorpholine and 1.27 ml isobutylchloroformate is added and the mixture is stirred at −15° C. for 20 minutes, whereupon 0.98 g of N,O-dimethylhydroxy/amine, HCl is added and the mixture is stirred overnight and the temperature is slowly elevated to room temperature. After aqueous work-up, 3β-tert-butyldimethylsilyloxy-4,4-dimethyl-5α-chola-8,14-dien-24-oic acid-N-methoxy-N-methyl amide (5.37 g) is obtained. Melting point: 134-135° C. 1H-NMR (CDCl3, 300 MHz): δ=5.35 (1H, s); 3.69 (3H, s); 3.2 (1H, m); 3.18 (3H, s); 0.9 (9H, s); 0.04 (6H, m).

Workup

additionis added
customis slowly elevated to room temperature

Sources & evidence

ORD record: ord-8b77c79f7d5a456e8d172f94c667cc2e
Source dataset: uspto-grants-2005_04
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06884796B2

Reaction notes

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