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) δ 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-84888d7bdf904eb2bf351d33cb69efa1

Quelldatensatz

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08415484B2