Synthesis method and application of JAK inhibitor drug compound

The invention discloses a synthesis method and application of a JAK inhibitor drug compound. The preparation method comprises the following steps: removing t-butyloxycarboryl from a compound A with a structure as shown in a formula (II) under the action of trifluoroacetic acid to obtain a compound B with a structure as shown in a formula (III); performing catalytic hydrogenation reduction on double bonds of the compound B by using palladium-carbon to obtain a trifluoroacetic acid intermediate (IV); the invention discloses a preparation method of a JAK inhibitor drug compound, which comprises the following steps: carrying out a first-step reaction on 2, 2-difluorocyclopropyl formic acid and N, N '-carbonyldiimidazole, and then adding a trifluoroacetic acid intermediate (IV) to carry out a second-step reaction, thereby obtaining the JAK inhibitor drug compound. The method provided by the invention has the advantages of greenness, economy and simplicity in operation, and is more suitable for industrial mass prod