Study On The Substitution Reaction Diversity Of Pentacoordinate Bisamino Hydrospirophosphoranes

Pentacoordinate phosphorus compounds, also called phosphoranes, are of veryactive chemical properties and can react with various nucleophilic reagentsinvolvingprotonsuch as water, alcohols, and amines. Being a special type ofpentacoordinate phosphorus compoundsand in a separate researching area,hydrospirophosphoranes have attracted much attention from scientists and are widelyinvestigated. The particularity of the structure is that at least one of the five chemicalbonds with phosphorus is P-H bond, which determines the distinctiveness of thechemical properties of hydrospirophosphoranesand mainly features in P-H bond. Ourgroup has successfully synthesized many kinds of pentacoordinate bisaminohydrospirophosphoranes, and the Atherton-Todd-typereaction of these compoundswith phenols, amines and CO2insertion reaction have been studied further. On thisbasis, in order to further expand the study on reaction activity ofpentacoordinatehydridophosphoranes, different single configuration of pentacoordinate bisaminohydrospirophosphoraneswere used as the research object to study theirAtherton-Todd-type reaction with sodium azide, sodium alcoholate and reaction withorganolithium compounds. The stereochemistry and mechanisms of the reactionswere proposed viadesigned experimental verification. By studying the spectroscopicproperties of pentacoordinate bisamino hydrospirophosphoranes derivativesandtheir absolute configurationsatphosphorus atoms,a method wasproposedto judgeabsolute configurations at phosphorus atom of pentacoordinate phosphoranesderivatives.Three reactions of pentacoordinate bisamino hydrospirophosphoranes withmetallic compounds were investigated. First of all, the reaction of thepentacoordinate bisamino hydrospirophosphoranes with sodium azide reaction wasstudied,and the related products were synthesized and the structure of the productswas characterizedvia NMR, ESI-MS and IR. The31P NMR tracking experimentswerecarried out to explore the stereochemistry and reaction mechanism.The results showed that the reactionwas mainly through a P-Cl intermediate,and theconfiguration at phosphorus atom of the intermediate was stereoretention,while theproducts wer stereoinversion. Secondly, the Atherton-Todd-type reaction ofpentacoordinate bisamino hydrospirophosphoraneswithsodium alcoholate wasinvestigated. By investigating the reaction pathway, the reaction mechanism wasproposed, namely that the alkoxy anions attackedphosphorus atom from twodirections to generate a pair of diastereoisomers. Finally the reaction ofpentacoordinate bisamino hydrospirophosphoraneswith organolithiumcompoundswas also studied and a series of products were separated andcharacterized.Based on analyzingthe spectroscopy properties of the pentacoordinatephosphoranesderivativesof certain configuration, the spectroscopy properties wereused to identify the absolute configuration at phosphorus atom of pentacoordinatephosphoranes derivatives. The investigation showedthat the value of3JCCNPin13CNMRand the absolute configuration at phosphorus atoms in those compounds have acertain correlation, and usually for a pair of diastereoisomers,3JCCNP(ΛP)>3JCCNP(ΔP).Using this rule to carry on the analysisthe spectroscopic properties of25compounds synthesized in this thesis, the configurations of those compoundswerededuced as expected.The results showed the feasibility of estimating absoluteconfigurationat phosphorus atoms based on the spectroscopy propertiesofpentacoordinate phosphorus compounds, which will contribute to further research ofstereochemistry properties of pentacoordinate phosphorus compounds.