Researches On The Reactions And Mechanisms Of Bisamino Hydrospirophosphoranes With Allylic Halides

Pentacoordinated organophosphoranes play a very important role in organophosphorous chemistry. Due to the active chemical nature and good biological activity, pentacoordinated organophosphoranes have been extensively investigated by lots of groups. Recently, the hydrospirophosphorane(HSP) bearing a P-H bond has attracted much attention because of the P-H bond resulting in the diversity of reaction. Especially, pentacoordinate bisamino hydrospirophosphoranes containing three chiral centers show a good stability. On the basis of the synthesis of a variety of pentacoordinate bisamino hydrospirophosphoranes, we have investigated the Atherton-Todd-type reactions of pentacoordinate bisamino hydrospirophosphoranes with phenols or amines. In order to study futher the reaction scope of pentacoordinate bisamino hydrospirophosphoranes, this thesis focuses on the reactions of pentacoordinate bisamino hydrospirophosphoranes with allylic halides.We optimized the reaction by screening a series of reaction conditions such as solvents, bases, temperature, the dosage of TBAI etc. With the opitimized condition in hand, the reaction of various pentacoordinate bisamino hydrospirophosphoranes with benzyl chloride has been firstly explored, which demonstrated that the smaller steric hindrance of pentacoordinate bisamino hydrospirophosphorane would result the faster reaction rate. Next, we investigated the reaction of pentacoordinate bi-valine hydrospirophosphorane with a series of alkyl halides, and the results showed that the types and steric hindrance of alkyl halides had a vital effect on the reaction rate. The structures of new compounds all characterized by NMR, IR and HRMS.In this paper, the reaction mechanism of the reaction of pentacoordinate bisamino hydrospirophosphorane with allylic halides was proposed, and 31 P NMR tracing was utilized to detect the reaction procedure. It is concluded that bisamino phosphoranide was produced first, which generated from pentacoordinate bisamino hydrospirophosphorane. Then the allylic halides attacked it via electrophilic substitution reaction. Finally, a series of new pentacoordinated spirophosphoranes with P-C bond were obtained.Based on the data of 1H-NMR, 13C-NMR, H-H COSY and C-H HMBC, the structure of the target compounds were confirmed, and the absolute configuration of the diastereomers was presumed by NOESY. The domin constructure presumed by NOESY had a constant relation with the result determined by coupling constant: JCCNP(ΔP) > JCCNP(ΛP). The discovery of the rule might have a potential application on verdicting the configuration of pentacoordinated spirophosphorane bearing P-C bond.