| α-Aminophosphonates,as phosphorus analogs of amino acids,and their derivativeshad attracted much attention for their broad biological activities,such as herbicide,antibacterial,enzymatic inhibitor,antiviral and antitumor activitives.Pudovik reaction is a well known reaction for the synthesis of phosphorus estercontaining a P-C bond by the addition of aldehyde to phosphonate.In this dissertation,agreen chemistry method was tried by using 25 % aqueous ammonia as the base catalystfor the Pudovik reaction.The products were purified by silica gel columnchromatography with the yields of 62-96 %.The merits of the reaction are the shortpath of synthesis,aqueous media substituted for the organic phase and easily purificationprocedure.The purified products includeα-aminophosphonates(A),α-hydroxyphosphonates(B),the derivatives ofα-amino phosphonates(C)and the derivatives ofα-hydroxyphosphonates(D).Their structures were confirmed by elemental analysis,1H NMR,13CNMR,31p NMR,MS and IR.The compounds contained P-C bonding with the couplingconstant 1JP-C154-168 Hz,which is consistent with the calculated value.Theirantibacterial and antitumor activities were tested in the experiments.The structures of thirty compounds were determined by X-ray diffractometer.Theircrystal parameters such as the crystal system,space group,unit cell dimension(a,b,c,α,β,γ),cell volume and limiting indices were obtained.And the structure information suchas atomic coordinates,equivalent isotropic displacement parameters,bond lengths,bondangles,torsion angles,hydrogen bond and packing figures were collected.These synthesized phosphonate esters were investigated by positive ionelectrospray ionization mass spectrometry(ESI-MS)in conjunction with tandem massspectrometry(MS/MS).It was found that for the sodium adduct there were two novel rearrangement reactions,in which phosphoryl oxygen atom migrated to the carbonylcarbon and a cleavage occurred at the amide bond,or a benzyl amine fragment was lostand the phosphorus compound was reduced.However,when the methyl groupsubstituted for the isopropyl group,these migrations were inhibited.A possiblemechanism was proposed.And the high-resolution mass spectrum was also applied toidentify the formula of these novel rearrange fragment ions.These results showed thatESI-MS is an useful tool for structural determination ofphosphonate ester.The ESI-MS technique was also applied to study on the weak non-covalentinteraction between ATP andα-aminophosphonates.In fluorescence experiment,thefluorescence intensity of ATP was quenched with the increasing concentration ofα-aminophosphonates.Molecular modeling also provided the possible interactionmodel,namely,there are two pairs of hydrogen bond between them.Furthermore,optical active L-Proline was used as catalysis in Pudovik reaction.Thereaction conditions were optimized in different solvent systems,bases,reactedtemperature and reactant molar ratio.The enantioselectivity through the derivatives ofL-Proline(G)is moderate.
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