Hydrochloric Acid → 3-(4-Pyridyl)-2-(4-fluorophenyl)-4,7-diaza-indole

Participants

Reaction Conditions

Reaction Steps

1-(4-Fluorophenyl)-2-t-butyldimethylsiloxy-2-(4-pyridyl) ethanone (16) (5.44 g, 15.77 mmol), 2-aminopyrazine (1.00 g, 10.5 mmol), and concentrated HCl (30 mL) were heated in a sealed tube to 190° C. behind an explosion shield. After 3 h at 190° C., the reaction was allowed to cool to 23° C. then diluted with water (100 mL). After further dilution with concentrated ammonium hydroxide to pH of 12, the reaction was extracted with methylene chloride (3×200 mL), and dried (MgSO4). After concentration in vacuo, the residue was purified by applying flash chromatography (100% ethyl acetate) to afford 3-(4-pyridyl)-2-(4-fluorophenyl)-4,7-diaza-indole (62): Mass Spectrum (CI) 291 (MH+).

Provenance & Evidence