1,1,1-Trimethoxybutane → HCID 57455398, compound

Participants

Reaction Steps

The preparation of ethyl 4-[(3-amino[1,5]naphthyridine-4-yl)amino]butyrate is described in Parts A-B of Example 4. Trimethyl orthobutyrate (9.1 mL, 57.2 mmol) and pyridine hydrochloride (110 mg, 0.95 mmol) were added to a solution of ethyl 4-[(3-amino-[1,5]naphthyridine-4-yl)amino]butyrate (13.08 g, 47.7 mmol) in toluene (190 mL) and heated at reflux for 3 hours. The reaction mixture was cooled to ambient temperature and concentrated under reduced pressure. The residue was dissolved in dichloromethane (200 mL) and washed with saturated aqueous sodium bicarbonate (150 mL). The aqueous layer was extracted with dichloromethane (2×50 mL). The combined organics were dried over magnesium sulfate, filtered, and concentrated under reduced pressure to afford 14.9 g of ethyl 4-(2-propyl-1H-imidazo[4,5-c][1,5]naphthyridin-1-yl)-butyrate as a yellow solid.

Provenance & Evidence