2-bromo-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carbaldehyde → 2-(5-methoxy-1-methyl-1H-indazol-3-yl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carbaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a 25 mL round-bottomed flask, 2-bromo-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carbaldehyde (439 mg, 1.23 mmol) and 5-methoxy-1-methyl-3-(tributylstannyl)-1H-indazole (556 mg, 1.23 mmol) were dissolved in DMF (3.00 mL) under argon, tetrakis(triphenylphosphine)palladium (0) (71.2 mg, 61.6 μmol) and CuI (46.9 mg, 246 μmol, Eq: 0.20) were added and the mixture sonicated for 5 min with bubbling argon. The reaction mixture was stirred at 90° C. (oil bath temperature) for 2.5 h. The reaction mixture was concentrated under high vacuum and the residue was purified by chromatography (80 g column, 50 μm from Analogix, 0-50% EtOAc in hexanes over 30 min) to give 2-(5-methoxy-1-methyl-1H-indazol-3-yl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carbaldehyde (443 mg, 1.01 mmol, 82.2%) as a yellow solid. MS (M+H)+=438 (>90% purity); 1H NMR (CDCl3) δ: 10.50 (s, 1H), 9.34 (s, 1H), 8.37 (d, J=2.3 Hz, 1H), 8.30 (s, 1H), 7.39 (d, J=9.1 Hz, 1H), 7.19 (dd, J=9.1, 2.3 Hz, 1H), 5.80 (s, 2H), 4.21 (s, 3H), 4.07 (s, 3H), 3.59-3.73 (m, 2H), 0.91-1.06 (m, 2H), 0.00 (s, 8H).

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