The Atherton-Todd Reaction Study Of Valine Hydrospirophosphorane

Pentacoordinated phosphoranes are very important in biological chemistry. Pentacoordinate phosphorus compounds as intermediates or transition-state species, are essential in numerous biological processes such as hydrolyses of RNA or phosphoryl transfer reactions. Hydrospirophosphorane(HSP) is a special type of pentacoordinate phosphoranes involving P-H bond, which is active enough to be precursors for organic synthesis. Houalla or Liu groups studied the Atherton-Todd reaction of the condensed bicyclic hydridophosphorane. Until now, there was no research on the Atherton-Todd reaction of hydrospirophosphoranes(HSP). Therefore, in this paper, we chose Valine Hydrospirophosphorane to study their Atherton-Todd reaction with amine or phenol-blocked.In the course of studying the Atherton-Todd reaction of Valine Hydrospirophosphorane with amine, we incidentally found that a carbon dioxide inserted carbamic spirophosphorane and a spirophosphorane ester were obtained. Moreover, we analyazed the impact of temperature, alkalis, chlorinating agent and nitrogen atmosphere on the reaction of Valine Hydrospirophosphorane with tertiary amine. In order to study the scope of this reaction, other amines such as secondary, primary amines were used. For secondary amines, not only carbamic spirophosphoranes and pyrophosphoranes but also aminospirophosphorane compounds were obtained. However, for primary amines only aminospirophosphorane compounds were produced. The structures of 18 novel compounds were identified by NMR, ESI-MS and IR.We continued to study the Atherton-Todd reaction of Valine Hydrospirophosphorane with phenol-blocked,12 novel spirophosphoranes were obtained in good yield which structures were determined by NMR, ESI-MS and IR. The MS/MS fragmentation characterizations of these novel spirophosphoranes were investigated in detail and their collision pathways were summarized.In addition, the Valine Hydrospirophosphorane was normaly a diastereoisomer, so we optimized the separateing condition. Furthermore, it was found that Valine Hydrospirophosphorane configurations cound be converted to each other when treated by base in the solvent. We stufdied the effects of bases and the volume of solvent on the convertion reaction, and found that base played an inportant role for the conversation. In the studing the stereochemistry characteristics of Valine Hydrospirophosphorane, the exchange phenomenon of N-H and N-D of Valine Hydrospirophosphorane was firtly observed by 31P NMR.