Preparation method of (R)-9-[2-(phosphonomethoxy) propyl] adenine

The invention relates to a preparation method of (R)-9-[2-(phosphonomethoxy) propyl] adenine. The preparation method comprises the steps of taking (R)-9-(2-hydroxypropyl) adenine as an initial compound and dissolving the (R)-9-(2-hydroxypropyl) adenine into DMF (dimethyl formamide), using lithium amide to participate in a reaction, slowly dropwise adding diethyl p-toluenesulfonyloxymethyl phosphonate, then, performing a heating reaction, and after treatment, using hydrobromic acid to remove ethyl, so as to obtain the (R)-9-[2-(Phosphonomethoxy) propyl] adenine. The initial material used by the preparation method is easy to obtain, safe and stable, the synthetic method is simple to operate, the product yield is high, the purity is high, the pollution to environment is relatively small, and a simple and feasible method is provided for the mass production of the compound, namely the (R)-9-[2-(Phosphonomethoxy) propyl] adenine.