Dimethylformamide → methyl 6-cyano-1-isopropyl-3-methyl-1H-indole-4-carboxylate

Beteiligte Stoffe

Reaktionsschritte

To a 10 ml microwave vial was added methyl 6-bromo-3-methyl-1-(1-methylethyl)-1H-indole-4-carboxylate (500 mg, 1.612 mmol), dicyanozinc (150 mg, 1.277 mmol) and DMF (5 mL). The mixture was degassed and stirred at rt under N2 for 15 min. To the mixture was added palladium tetrakis (118 mg, 0.102 mmol) and the reaction was stirred at 95° C. for 1 h. The reaction was allowed to cool and poured into saturated aqueous Na2CO3 (50 mL) and EtOAc (50 mL) and stirred for 20 min. The mixture was extracted with ether (100 ml) and EtOAc (100 ml) (1:1), followed by filtration and evaporation to yield a residue. The residue was purified by silica gel chromatography (Analogix IF280, 0-8% EtOAc/hexanes, SF25-40 g, 30 minutes) to give methyl 6-cyano-3-methyl-1-(1-methylethyl)-1H-indole-4-carboxylate (130 mg, 0.497 mmol, 38.9% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.38 (d, J=1.52 Hz, 1H) 7.82 (s, 1H) 7.71 (d, J=1.52 Hz, 1H) 4.85-4.97 (m, 1H) 3.90 (s, 3H) 2.29 (s, 3H) 1.45 (d, J=6.57 Hz, 6H). MS(ES) [M+H]+ 257.4.

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