Synthesis of Aminopyrine

Synthesis of Aminopyrine

Commercial Method
Aminopyrine can be synthesized commercially by treating antipyrine with HNO₂ to yield nitrosoantipyrine which reduced to aminoantipyrine with Zn/AcOH. Now aminoantipyrine is treated with two moles of chloroacetic acid followed by decarboxylation gives the official product Aminopyrine. Aminoantipyrine can be directly methylated to aminopyrine with methyl iodide in Me₂SO₄ solution.
Laboratory Method
Aminopyrine can be prepared in the laboratory by treating antipyrine with bromine to obtain 4-bromoantipyrine which on subsquent treatment with dimethylamine yield the aminipyrine.