反应详情

A mixture of ethyl 6-ethyl-4-hydroxy-1,5-naphthyridine-3-carboxylate (3.0 g) and phosphorus oxychloride (25 ml) was stirred and heated at 40°-50° C. for 1 hour. The mixture was then cooled and then worked up as described in Example B1 to give ethyl 4-chloro-6-ethyl-1,5-naphthyridine-3-carboxylate, m.p. 94°-96° C.

1. temperatureheated at 40°-50° C. for 1 hour
2. temperatureThe mixture was then cooled