Sodium Bicarbonate → ethyl 5-methoxy-4-methyl-1H-indole-2-carboxylate

Temperatur

65 °C

To a reaction mixture of ethyl 4-bromo-5-methoxy-1H-indole-2-carboxylate (1 g, 3.35 mmol) and bis(tri-t-butylphosphine)palladium (0) (0.171 g, 0.335 mmol) in THF (10 mL) was added a 2 M solution of methylzinc(II) chloride in THF (5.03 mL, 10.06 mmol) at room temperature. The reaction was stirred at 65° C. for 2 h, cooled down, and added saturated aqueous NaHCO3 solution. The solid was filtered off through celite and washed with ethyl acetate. The filtrate was extracted with ethyl acetate. The combined organics were dried over anhydrous Na2SO4 and concentrated. The residue was purified by silica gel column chromatography to give the title compound as white solid (712 mg). LCMS m/z=234.2 [M+H]+; 1H NMR (400 MHz, CDCl3) α ppm 1.42 (t, J=7.1 Hz, 3H), 2.44 (s, 3H), 3.87 (s, 3H), 4.41 (q, J=7.1 Hz, 2H), 7.05 (d, J=9.0 Hz, 1H), 7.19-7.24 (m, 2H), 8.81 (s, 1H).

1. temperaturecooled down
2. filtrationThe solid was filtered off through celite
3. washwashed with ethyl acetate
4. extractionThe filtrate was extracted with ethyl acetate
5. dry with materialThe combined organics were dried over anhydrous Na2SO4
6. concentrationconcentrated
7. customThe residue was purified by silica gel column chromatography

ORD-Eintrag

ord-46fbe6ab6439465c85d3844b6ea2bce5

Quelldatensatz

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09108969B2