p-Toluenesulfonic acid → (S)-tert-Butyl 4-((R)-2-(hydroxymethyl)pent-4-en-1-yl)-2,2-dimethyloxazolidine-3-carboxylate

HRID 2039930Notes

Reaction equation

[OH:1][CH2:2][C@@H:3]([NH:11][C:12](=[O:18])[O:13][C:14]([CH3:17])([CH3:16])[CH3:15])[CH2:4][C@H:5]([CH2:9][OH:10])[CH2:6][CH:7]=[CH2:8].[CH3:19][C:20]1C=CC(S(O)(=O)=O)=C[CH:25]=1.COC(OC)(C)C>CC(C)=O>[OH:10][CH2:9][C@H:5]([CH2:6][CH:7]=[CH2:8])[CH2:4][C@H:3]1[CH2:2][O:1][C:20]([CH3:25])([CH3:19])[N:11]1[C:12]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:18]

Participants

Conditions

Temperature: -20 °C

Procedure

To a solution of tert-butyl (2S,4R)-1-hydroxy-4-(hydroxymethyl)hept-6-en-2-ylcarbamate (6.8 g, 26.2 mmol) in acetone (150 mL), PTSA (0.45 g, 2.62 mmol) was added. The reaction mixture was cooled to −20° C. followed by the addition of 2,2-dimethoxypropane (4.1 g, 39.4 mmol). The resulting mixture was stirred and allowed to warm to rt for 1 hr. TEA (0.5 mL) was then added and stirred for another 5 min. The solvent was removed under reduced pressure. The residue was dissolved in Et2O (300 mL), washed with 1N HCl (80 mL), sat. aq. NaHCO3 (80 mL), brine (80 mL) successively, and dried, filtered, and concentrated under vacuum to give crude (S)-tert-butyl 4-((R)-2-(hydroxymethyl)pent-4-enyl)-2,2-dimethyloxazolidine-3-carboxylate (7.5 g, 96%). It was used without further purification.

Workup

temperatureto warm to rt for 1 hr
stirringstirred for another 5 min
customThe solvent was removed under reduced pressure
dissolutionThe residue was dissolved in Et2O (300 mL)
washwashed with 1N HCl (80 mL), sat. aq. NaHCO3 (80 mL), brine (80 mL) successively
customdried
filtrationfiltered
concentrationconcentrated under vacuum

Sources & evidence

ORD record: ord-17665450bfb74640b97d5884657bee6b
Source dataset: uspto-grants-2013_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08580823B2

Reaction notes

Loading…