Hydrochloric Acid → 5-Chloro-8-[(6-methoxy-pyridin-3-yl)-methyl]-[1,6]naphthyridine

Participants

Reaction Steps

396 mg (1.48 mmol) of 8-[(6-methoxy-pyridin-3-yl)-methyl]-6H-[1,6]naphthyridin-5-one in 24 ml of acetonitrile are mixed, whilst excluding air, with 1.4 ml (15 mmol) of phosphorus oxychloride and 0.78 ml of 4 N HCl in dioxan and stirred for 96 h at 65° C. After cooling to RT, partial concentration by evaporation takes place on a RE, then 40 ml of ice water and 10 ml of NH3 solution are added and extraction carried out 3 times with EtOAc. The organic phases are washed with water and brine, dried (Na2SO4) and concentrated by evaporation to form 5-chloro-8-[(6-methoxy-pyridin-3-yl)-methyl]-[1,6]naphthyridine (contaminated with a little 5-chloro-8-[(6-chloro-pyridin-3-yl)-methyl]-[1,6]naphthyridine); FAB-MS: (M+H)+=286; HPLC(gradients20-100) tRef=10.2.

Provenance & Evidence