Synthesis method of ruthenium carbene catalyst

The invention relates to a synthesis method of a ruthenium carbene catalyst, which comprises the following steps: (1) adding benzyl halide and triphenylphosphine into a reactor, reacting in a medium,and reacting the obtained reaction product under the action of a strong alkali to obtain a first intermediate product; (2) reacting the first intermediate product with triphenylphosphine ruthenium chloride in a solvent, replacing triphenylphosphine with tricyclohexylphosphine, filtering and washing to obtain a ruthenium carbene complex precursor; and (3) carrying out a complex addition reaction onthe ruthenium carbene complex precursor and a functional ligand to obtain the target product that is the ruthenium carbene catalyst. Compared with the prior art, the method has the characteristics ofcapability of efficiently controlling the reaction speed, short preparation period, simplicity in operation, stable process, environmental friendliness, good atom economy and the like, and has a relatively great application pr