Triethylamine → 1-isopropyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid

Beteiligte Stoffe

Reaktionsschritte

To a 100 mL round bottom flask was charged 10% Pd/C(degussa) (0.213 g, 0.100 mmol), under N2 followed by addition of ca. 5 mL EtOH. The slurry was stirred followed by addition of 6-chloro-1-(1-methylethyl)-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (0.48 g, 2.003 mmol) and ethanol (22 mL). Next added Et3N (0.837 mL, 6.01 mmol) and stirred for 5 min under nitrogen. The contents were then stirred under an atmosphere of hydrogen (1 atm) for 6 h at RT. The vessel was then flushed with nitrogen and the contents diluted with DCM (10 mL) and a small amount of celite. The contents were stirred for 10 min., filtered through analytical grade celite and washed with 10% MeOH/DCM, EtOH, then DCM. The filtrate was concentrated in vacuo to a residue and dried on hi-vacuum overnight. The solid was treated with water and adjusted to pH 3 with 1M HCl. The contents were filtered, air-dried and then dried in hi-vacuum oven at 45° C. for 18 h. The title compound was collected as 0.326 g (78%). 1H NMR (400 MHz, DMSO-d6) δ ppm 1.52 (d, J=6.82 Hz, 6 H) 5.28 (quin, J=6.69 Hz, 1 H) 7.70 (d, J=4.55 Hz, 1 H) 8.39 (s, 1 H) 8.73 (d, J=4.55 Hz, 1 H) 13.91 (br. s., 1 H). LCMS(ES) [M+H]+ 205.9

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