Cesium carbonate → 6-(6-Bromo-imidazo[1,2-a]pyridin-8-ylamino)-3',4',5',6'-tetrahydro-2'H-[3,4']bipyridinyl-1'-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 6-amino-3′,4′,5′,6′-tetrahydro-2′H-[3,4′]bipyridinyl-1′-carboxylic acid tert-butyl ester (971 mg, 3.0063 mmol), 6-bromo-8-iodo-imidazo[1,2-a]pyridine (1 g, 3.6075 mmol), Pd2(dba)3 (138 mg, 0.1503 mmol), XantPhos (174 mg, 0.3006 mmol), and Cs2CO3 (2 g, 6.0126 mmol) were combined in dioxane (20 mL) and the solution was stirred at 90° C. under N2 atmosphere for 5 h at which point the TLC showed little starting material remained. The solution was poured onto water and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over Na2SO4, and concentrated. Purification by column chromatography on silica gel (DCM: MeOH, 60:1 eluent) afforded the desired product as yellow solid (1.15 g, 81%). 1H NMR (300 MHz, CDCl3): δ 8.44 (d, J=1.5 Hz, 1H), 8.20 (d, J=2.1 Hz, 1H), 7.92 (s, 1H), 7.84 (d, J=1.5 Hz, 1H), 7.49 (s, 2H), 7.42 (dd, J=8.4, 2.4 Hz, 1H), 6.84 (d, J=8.4 Hz, 1H), 4.27-4.23 (m, 2H), 2.85-2.77 (m, 2H), 2.68-2.58 (m, 1H), 1.84-1.79 (m, 2H), 1.67-1.57 (m, 2H), 1.48 (s, 9H).

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