Separation of 5-nitroquinoline and 8-nitroquinoline

摘要

The present invention relates to a process for preparing 5-nitroquinoline hydrohalide comprising:(A) heating a slurry comprising a mixture of nitroquinoline position isomer hydrohalide salts in wet dimethylformamide to form a solution;(B) cooling the solution of Step (A) until a precipitate comprising 5-nitroquinoline hydrohalide is formed; and(C) collecting the precipitate.