4-Chlorophenylboric acid is an important pharmaceutical intermediate. There are three traditional preparation methods: (1) organic lithium reagent method, (2) Grignard reagent method, and (3) catalytic boration method.

The organic lithium reagent method has high yield and few by-products, but it is not suitable for industrial production because of its high safety and high cost of raw materials. The catalytic boration method was derived after the discovery of suzuki coupling reaction, and has good adaptability to various groups. However, the raw materials and noble metal catalysts are expensive, and the requirements for high-purity compounds, so there are still many problems to be solved to realize industrial conversion. At present, Grignard reagent method is a relatively common method in industry. It is difficult to initiate the preparation of p-chlorobenzoic acid Grignard reagent through Grignard reaction. Some need to use mixed solvents. The solvent cost in this preparation process is too high, accounting for about 20-50%. In the production process of 4-chlorophenylboric acid, brominated aromatics are often used as raw materials. Because the molecular weight of bromine is much larger than that of chlorine, the cost is directly too high, and brominated compounds not only pollute the environment greatly, but also produce a lot of magnesium salt solid waste.

So how to reduce the solvent cost, simplify the process, improve the conversion rate and reduce the amount of solid pollutants has been a series of technical problems in industrial production.