Scheme 4.
Synthesis of Chloronaphthyridinonesa
aReagents and conditions: (a) POCl3, DMF, room temperature to 70 °C, 7 h (61%); (b) POCl3, PCl5, room temperature, 1 h, reflux, 1.5 h (66%).
Synthesis of Chloronaphthyridinonesa
aReagents and conditions: (a) POCl3, DMF, room temperature to 70 °C, 7 h (61%); (b) POCl3, PCl5, room temperature, 1 h, reflux, 1.5 h (66%).