HCID 45140499, compound → HCID 68768173, compound

Temperature

-20 °C

To a cooled (−40° C.) solution of (E)-1,2,4-trifluoro-5-(2-nitrovinyl)benzene (250 g, 1.23 mol) in THF (490 mL), allylmagnesium chloride (800 mL, 1.6 mol, 2 M in THF) was added at such a rate as to maintain the internal temperature below −20° C. The solution was stirred at −20° C. for thirty minutes and then carefully quenched by the addition of 2M HCl (1 L), while maintaining the temperature below −5° C. Methyl t-butyl ether (500 mL) was added, and the biphasic solution was allowed to warm to >10° C. The layers were separated, and the organic was washed with H2O (1×500 mL), saturated aqueous NaHCO3 (1×500 mL), and brine (1×500 mL). The organic layer was concentrated to dryness, and the crude product was filtered through a 450 g plug of silica gel (eluting with 5% ethyl acetate in hexane at a flow rate of 90 mL/min). The first 100 mL of eluent was discarded, and the subsequent 2 L were collected and concentrated to dryness to give the title compound as an oil (268 g, 89%). 1H NMR (300 MHz, CDCl3) δ ppm 7.05-6.90 (m, 2H), 5.65 (dddd, J=7.5, 7.5, 9.5, and 16.6, Hz, 1H), 5.12-5.06 (m, 2H), 4.63 (d, J=7.5 Hz, 2H), 3.75 (p, J=7.5 Hz, 1H), and 2.48 (t, J=7.5 Hz, 2H).

1. additionwas added at such a rate as
2. temperatureto maintain the internal temperature below −20° C
3. customcarefully quenched by the addition of 2M HCl (1 L)
4. temperaturewhile maintaining the temperature below −5° C
5. additionMethyl t-butyl ether (500 mL) was added
6. temperatureto warm to >10° C
7. customThe layers were separated
8. washthe organic was washed with H2O (1×500 mL), saturated aqueous NaHCO3 (1×500 mL), and brine (1×500 mL)
9. concentrationThe organic layer was concentrated to dryness
10. filtrationthe crude product was filtered through a 450 g plug of silica gel (
11. washeluting with 5% ethyl acetate in hexane at a flow rate of 90 mL/min)
12. customthe subsequent 2 L were collected
13. concentrationconcentrated to dryness

ORD record

ord-ab3fae8c7b494ef3bccff073701a2533

Source dataset

uspto-grants-2010_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07834012B2