Preparation method of 2-chloro-4-nitrobenzene-alpha-L-fucoside

The invention discloses a preparation method of 2-chloro-4-nitrobenzene-alpha-L-fucoside, and belongs to the field of in vitro diagnosis. The preparation method comprises the following steps: taking L-fucose as an initial raw material, carrying out acetylation reaction to prepare 1, 2, 3, 4-tetraacetyl-alpha-L-fucose, and then carrying out glycosylation reaction on the 1, 2, 3, 4-tetraacetyl-alpha-L-fucose and 2-chloro-4-nitrophenol to prepare the 2-chloro-4-nitrobenzene-2, 3, 4-triacetyl-alpha-L-fucoside, the catalyst is selected from Trimethylsilyl trifluoromethanesulfonate or Boron trifluoride ethyl ether; and finally, carrying out a deacetylation reaction, so as to prepare the 2-chloro-4-nitrobenzene-alpha-L-fucoside. The method disclosed by the invention is relatively short in reaction route, and the final product is prepared through three-step reaction; L-fucose is used as the raw material, the price of the initial raw material is relatively low, and the dosage of 2-chloro-4-nitrophenol is obviously red