Preparation method of 2-ethyl-4-cyanopyridine

The invention provides a preparation method of 2-ethyl-4-cyanopyridine. According to the preparation method, 1-(4-bromopyridin-2-yl)ethanone is used as an initial raw material, 2-ethyl-4-bromopyridineis prepared through reduction of a catalyst and a reducing agent, and 2-ethyl-4-cyanopyridine is obtained through cyanation. The total yield is 85% or more, and the product purity is 99% or more. Theroute is simple and convenient, auxiliary materials are common compounds, and the solvent can be recycled. The product is a single compound. Compared with a traditional synthesis method, the synthesis method has the advantages that isomer 3-ethyl-4-cyanopyridine is not generated, and the requirement for post-treatment of synthesis of ethylthio isonicotinamide is low. The synthetic route is safe,simple and convenient to operate, environment-friendly, capable of relaxing the bowels and suitable for industrial production. 本发明提供了一种2-乙基-4-氰基吡啶的制备方法。该制备方法以1-（4-溴吡啶-2-基）乙酮为起始原料，通过催化剂和还原剂还原制备2-乙基-4溴吡啶，通过氰基化得到2-乙基-4-氰基吡啶。总收率在85