Method of synthesizing 25-hydroxy cholesterol

A method for synthesizing 25-hydroxy cholesterol, comprising:

• adding a 24-dehydrocholesterol derivative and a hydroxyl containing reagent to an organic solvent and react at −40° C.-150° C. for 1-40 hours in the presence of a catalyst;
• after completing the reaction, hydrolyzing with alkali, and then separating the reaction solution to obtain 25-hydroxy cholesterol, wherein the structural formulas of the 25-hydroxy cholesterol, the 24-dehydrocholesterol derivative and the hydroxyl containing reagent are shown in formula (I), formula (II) and formula (III) respectively:
• the R1 in formula (II) is the same as the R2 in formula (III), which is H or C1-C12 acyl group,
• wherein the hydroxyl containing reagent is one of water, formic acid, acetic acid, propionic acid, butyric acid, benzoic acid and p-methyl benzoic acid or a mixture thereof at any ratio,
• wherein the catalyst is one of sulfuric acid, phosphoric acid, p-toluenesulfonic acid, sodium bisulfate, potassium bisulfate, phosphorus pentoxide, aluminum trichloride, titanium tetrachloride, ferric trichloride, nickel chloride, cobalt chloride, zinc chloride, magnesium chloride, calcium chloride, aluminum tribromide, ferric tribromide, zinc bromide, magnesium bromide, magnesium iodide, scandium trifluoromethanesulfonate, lanthanum trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, iridium methanesulfonate, neodymium trifluoromethanesulfonate, samarium trifluoromethanesulfonate, zinc trifluoromethanesulfonate, gallium trifluoromethanesulfonate, copper trifluoromethanesulfonate, gold trifluoromethanesulfonate, silver trifluoromethanesulfonate or indium trifluoromethanesulfonate.