Homoallyl bromide → 3-(3-Buten-1-YL)-2-pyrrolidinone

Temperature

0 °C

DIPEA (0.393 mL, 2.76 mmol) was dissolved in THF (25 mL) and chilled to −78° C. n-Butyllithium (1.10 mL, 2.76 mmol) was then added, and the reaction was warmed to 0° C. and re-chilled to −78° C. 1-(tert-Butyldimethylsilyl)pyrrolidin-2-one (0.500 g, 2.51 mmol) was then added as a solution in THF (1 mL), and the reaction mixture was warmed to room temperature for 1 hour. The reaction was then re-cooled to −78° C., and 4-bromobut-1-ene (0.305 mL, 3.01 mmol) was added dropwise in THF (1 mL). The reaction mixture was slowly warmed to room temperature overnight. The reaction was concentrated to an oil and loaded onto CELITE®. Purification by flash column chromatography using 0-30% acetone/hexanes provided the title compound (0.218 g, 62%): 1H NMR (400 MHz, CDCl3) δ 6.15 (s, 1H), 5.82 (ddt, J=17.0, 10.2, 6.6 Hz, 1H), 5.09-4.87 (m, 2H), 3.42-3.24 (m, 2H), 2.44-2.25 (m, 2H), 2.24-2.05 (m, 2H), 1.99 (dddd, J=13.6, 9.4, 6.9, 4.1 Hz, 1H), 1.78 (dq, J=12.1, 8.4 Hz, 1H), 1.45 (dtd, J=13.7, 9.1, 5.5 Hz, 1H); 13C NMR (101 MHz, CDCl3) δ 180.44, 137.92, 115.13, 40.29, 40.16, 31.45, 30.05, 27.60; ESIMS m/z 138 ([M−H]−).

1. additionwas then added
2. temperaturere-chilled to −78° C
3. temperaturethe reaction mixture was warmed to room temperature for 1 hour
4. temperatureThe reaction was then re-cooled to −78° C.
5. temperatureThe reaction mixture was slowly warmed to room temperature overnight
6. concentrationThe reaction was concentrated to an oil
7. customPurification by flash column chromatography

ORD record

ord-078caf9a7fba471c8254178546417f4a

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09295260B2