1,2-Dibromoethane → HCID 13541935, compound

Temperature

-78 °C

To a cooled (-78° C.) solution of TMEDA (787 mg, 6.6 mmol) in anhydrous THF (15 mL) was slowly added sec-butyl lithium (130 M, 5.08 mL, 6.6 mmol), and the resultant solution was stirred at -78° C. for 10 minutes. 3-Pyridyl diethylcarbamate (1.16 g, 6.0 mmol, from step 20a) in THF (3 mL) was slowly added, and the mixture was stirred at -78° C. for 30 minutes. 1,2-Dibromoethane (0.575 mL, 6.6 mmol) was then added, and the mixture was stirred for an additional 2 hours. Brine (1 mL) was added and the mixture was slowly warmed up to room temperature. The organic layer was decanted, and the residue was washed with ethyl acetate (3×5 mL). The combined organic layers were dried (Na2SO4) and concentrated under reduced pressure. The crude product was purified by flash chromatography on silica gel eluting with hexane/EtOAc (1:1 and 1:2) to provide 1.25 g (76% yield) of the title compound. TLC Rf 0.48 (1:2 hexane/EtOAc). MS (DCI/NH3) m/e 290 with 79Br and 292 (M+NH4)+ with 81Br, 273 with 79Br and 275 (M+H)+with 81Br. 1H NMR (CDCl3, 300 MHz) δ: 8.47 (s, 1H, ArH), 8.27 (d, J=7.2 Hz, 1H, ArH), 7.16 (d, J=7.2 Hz, 1H, ArH), 3.52 (q, J=7.5 Hz, 2H, NCH2), 3.41 (q, J=7.5 Hz, 2H, NCH2), 1.33 (t, J=7.5 Hz, 3H, CH3), 1.24 (t, J=7.5 Hz, 3H, CH3).

1. stirringthe mixture was stirred for an additional 2 hours
2. temperaturethe mixture was slowly warmed up to room temperature
3. customThe organic layer was decanted
4. washthe residue was washed with ethyl acetate (3×5 mL)
5. dry with materialThe combined organic layers were dried (Na2SO4)
6. concentrationconcentrated under reduced pressure
7. customThe crude product was purified by flash chromatography on silica gel eluting with hexane/EtOAc (1:1 and 1:2)

ORD record

ord-f4d3b99f855c45a8ada5ae7a7e620989

Source dataset

uspto-grants-1999_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05914328