Synthetic method of 4-(2,2-difluoro-1,3-benzodioxole-4-yl)pyrrole-3-nitrile

The invention discloses a synthetic method of 4-(2,2-difluoro-1,3-benzodioxole-4-yl)pyrrole-3-nitrile. The method comprises the following steps of: preparing an intermediate 2,2-difluorobenz-1,3-dioxole through reacting catechol with dibromodifluoromethane, and preparing an intermediate 2-cyano-3-(2,2-difluorobenz-1,3-dioxole-4-yl)-2-acrylate. The fludioxonil prepared by the synthetic method provided by the invention has the purity of more than 99.0% and the total yield of more than 45.0%; the synthetic method has the advantages of cheap and easily available raw materials, simple process, high product yield in each step, good purity, low production cost, applicability to batch industrial production and the like.