Dimethylformamide → HCID 131723393, compound

Temperature

-78 °C

To a solution of 2-allyldimethylsilylthiophene (1 Scheme 28, 10.6 g, 58.5 mmol) in dry THF (300 mL) at −78° C. was added n-butyllithium (23.4 mL, 2.5 M solution in hexanes, 58.5 mmol) over a period of 10 min. After 30 min stirring at −78° C., anhydrous DMF (6.8 mL, 87.8 mmol) was added dropwise. The reaction mixture was stirred further for 1 h and warmed to room temperature. Concentrated NH4Cl (4 mL) was added to the solution, and the reaction mixture was concentrated. The residue was extracted with ethyl acetate (150 mL) and brine (20 mL), and the organic layer was dried (Na2SO4) and concentrated to afford a colorless oil (12.1 g, 98%); 1H NMR (300 M CDCl3) δ 0.32 (s, 6 H), 1.76 (dd, J=8.10, 1.20 Hz, 2 H), 4.85 (m, 1 H), 4.89 (s, 1 H), 5.72 (m, 1 H), 7.30 (d, J=3.60 1 H), 7.77 (dd, J=3.60, 1.50 Hz, 1 H), 9.90 (s, 1 H); 13C NMR (75 MHz, CDCl3) −2.4 (2C), 24.0, 114.9, 133.3, 135.4, 137,0, 148.7, 150.7, 182.7; HRMS (EI) calcd for C10 H14OSSi 210.0533, found 210.0531.

1. stirringThe reaction mixture was stirred further for 1 h
2. temperaturewarmed to room temperature
3. concentrationthe reaction mixture was concentrated
4. extractionThe residue was extracted with ethyl acetate (150 mL) and brine (20 mL)
5. dry with materialthe organic layer was dried (Na2SO4)
6. concentrationconcentrated

ORD record

ord-62779e17773f46e2a04d258abdea2d18

Source dataset

uspto-grants-2002_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06416861B1