Phosphorus oxychloride → 1-Chloro-2,6-naphthyridine

Participants

Reaction Conditions

Reaction Steps

Under stirring, 184 ml (2.00 mol) phosphorus oxychloride was added slowly to a suspension of 146 g (1.00 mol) 2,6-naphthyridine-1(2H)-one in 1500 ml chlorobenzene at room temperature. The reaction mixture was heated to 100° C., stirred at this temperature for 16 hours and then cooled to room temperature. The solids were filtered off, washed with chlorobenzene and dried under vacuum. The residue was taken up in 1.5 l ice-cold water, 350 ml 50% aqueous sodium hydroxide solution to reach a pH value of 7-8. The precipitate thus formed was filtered off, washed with water and dried under vacuum yielding 1-chloro-[2,6]naphthyridine as brown crystals; HPLC/MS (A): 1.62 min, [M+H] 165.

Provenance & Evidence