Cabozantinib intermediate 4-hydroxy-6,7-dimethoxyquinoline and preparation method thereof

The invention provides a cabozantinib intermediate 4-hydroxy-6,7-dimethoxyquinoline and a preparation method thereof. According to the method, ortho-formate, isopropylidene malonate and 3,4-dimethoxyaniline used as raw materials are subjected to condensation and cyclization reaction to obtain the 4-hydroxy-6,7-dimethoxyquinoline. The chemical reaction conditions are milder; the yield for each reaction is up to 90% or so; and the total product yield is 71.3-79.3%. The method has the advantages of cheap and accessible raw materials, high safety, low toxicity, environment friendliness and simple preparation technique, and is suitable for industrial production.