Diisopropylethylamine → Ethyl acetate hexane

Temperature

-78 °C

A solution of (R)-4-benzyl-3-(2-(3-fluoro-4-(trifluoromethyl)phenyl)acetyl)oxazolidin-2-one (1.6 g, 4.20 mmol) was dissolved in dichloromethane (40 mL), cooled to −78° C. and treated slowly with titanium (IV) chloride (4.4 mL, 4.40 mmol). This was followed by treatment with diisopropylethylamine (0.76 mL, 4.36 mmol). The mixture was stirred at −78° C. for 15 minutes, and tert-butyl 2-methoxypyrrolidine-1-carboxylate (1.0 g, 4.97 mmol) was added. After 15 minutes, the reaction was allowed to warm to ambient temperature for one hour. The reaction was quenched with saturated NH4Cl (20 mL) and extracted with dichloromethane (3×100 mL). The organic phase was dried over Na2SO4 and concentrated in vacuo. The residue was purified by column chromatography, eluting with hexane/ethyl acetate (4:1), (1.44 g, 62.3% yield). 7.55 (t, J=8.2, 1H), 7.38-7.18 (m, 7H), 5.61-5.51 (m, 1H), 4.72-4.56 (m, 2H), 4.16-4.02 (m, 2H), 3.43-3.34 (m, 1H), 3.28-3.15 (m, 1H), 2.77-2.61 (m, 1H), 1.96-1.80 (m, 1H), 1.75-1.56 (m, 4H), 1.48 (s, 9H).

1. waitAfter 15 minutes
2. temperatureto warm to ambient temperature for one hour
3. customThe reaction was quenched with saturated NH4Cl (20 mL)
4. extractionextracted with dichloromethane (3×100 mL)
5. dry with materialThe organic phase was dried over Na2SO4
6. concentrationconcentrated in vacuo
7. customThe residue was purified by column chromatography

ORD record

ord-ec83df5f2abd4d88979b5a4a20d911b6

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08618097B2