Boron trifluoride etherate → (2S,4R)-4-tert-butoxy-1-(naphthalene-2-sulfonyl)-pyrrolidine-2-carboxylic acid benzyl ester
Reaktionsgleichung
[CH2:1]([O:8][C:9]([C@@H:11]1[CH2:15][C@@H:14]([OH:16])[CH2:13][N:12]1[S:17]([C:20]1[CH:29]=[CH:28][C:27]2[C:22](=[CH:23][CH:24]=[CH:25][CH:26]=2)[CH:21]=1)(=[O:19])=[O:18])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.B(F)(F)F.CCOCC.[CH3:39][C:40](=[CH2:42])[CH3:41].C(=O)(O)[O-].[Na+]>ClCCl>[CH2:1]([O:8][C:9]([C@@H:11]1[CH2:15][C@@H:14]([O:16][C:40]([CH3:42])([CH3:41])[CH3:39])[CH2:13][N:12]1[S:17]([C:20]1[CH:29]=[CH:28][C:27]2[C:22](=[CH:23][CH:24]=[CH:25][CH:26]=2)[CH:21]=1)(=[O:19])=[O:18])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Komponenten
Edukt 4
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Reaktionsbedingungen
- Temperatur
- -20 °C
Versuchsvorschrift
Tert-Butyletherification: To a solution of (2S,4R)-4-hydroxy-1-(naphthalene-2-sulfonyl)-pyrrolidine-2-carboxylic acid benzyl ester (14.8 g) in dichloromethane (140 ml) were added boron trifluoride ethyl etherate (3 ml) and isobutylene (cooled and liquefied at −30° C., 170 ml) at −30° C. The turbid reaction mixture was stirred at −20° C. for 2 h, poured onto a saturated sodium bicarbonate solution, and extracted with dichloromethane. The organic phases were washed with water, dried over magnesium sulphate and concentrated. The residue was chromatographed on silica gel using EtOAc/hexane 1:4 and 1:2 as eluents to obtain (2S,4R)-4-tert-butoxy-1-(naphthalene-2-sulfonyl)-pyrrolidine-2-carboxylic acid benzyl ester (16.4 g) as a glassy syrup, MS: 467 (M).
Aufarbeitung
- customThe turbid reaction mixture
- extractionextracted with dichloromethane
- washThe organic phases were washed with water
- dry with materialdried over magnesium sulphate
- concentrationconcentrated
- customThe residue was chromatographed on silica gel
Quellen und Nachweise
- ORD-Eintrag
- ord-ec731da895bb443e99c66ab6b5e97401
- Quelldatensatz
- uspto-grants-2004_09
- Patentnummer
- US06790860B2
Notizen zur Reaktion
Wird geladen…