Applications Of H-phosphonates In Synthesis Of Substituted Phosphonomethylbenzenes And Peptide Analogs

H-phosphonates is an important part of organophosphorus compounds. A formof tautomerizm behavior makes H-phosphonates have the merits of P(V)compounds and P(III) compounds together, so more and more chemists are interestedin H-phosphonate chemistry. H-phosphonates have been used to synthesizenucleosides analoges, peptide analoges, lipid analoges and so on. In this dissertation,applications of H-phosphonates have been explored in synthesis of substitutedphosphonomethylbenzenes, peptide analogs and heterocycles.A simple, efficient and general method has been developed for synthesis of4-(phosphonomethyl)benzene derivatives through one-pot reaction of phosphoric acid,4-substitute benzyl chlorides and hexamethyldisilazane under solvent-free conditionsand the following hydrolysis in 2M NH3·H2O. Compared with other methodologies,this method is convenient, high yield and economic. It can be used to synthesize othercompounds containing P-C bond. In this method, H-phosphonate acted as the donatorof phosphoryl group.Various amides including dipeptides and their analogs have been synthesized inexcellent yields using diphenyl phosphite as the coupling reagent. This method is fast,general, high yielding, and no racemization is observed. H-phosphonate became anefficient coupling reagents in the method.An efficient method has been developed for the preparation of 6-12 memberednitrogen heterocycles via copper-catalyzed intramolecular N-arylation ofphosphoramidates. The phosphoryl acted as the protecting group of amino in theformation of amides. The phosphoramide group improved intramolecular cyclizationduring the cyclization process, and the phosphoryl can easily be removed under themild condition, so the convenient and efficient method can be generally used toprepare middle-sized nitrogen heterocycles, which makes the method a newdevelopment of transition metal catalysis. H-phosphonate became a phosphorylatingagent to afford the phosphoryl group, which play a role of temporary protective groupin the reactions and enhanced the intramolecular cyclization.