N-Thiophosphorylated andN-Phosphorylated Iminophosphoranes [R3P=N–P(X)R′2; × = O, S] as Models for Dendrimers: Synthesis, Reactivity and Crystal Structures
Reactivity of Ph3PNLi towards PIII and PV electrophiles
作者:Nicolas J. Rahier、Jean-Noël Volle、Marie Agnès Lacour、Marc Taillefer
DOI:10.1016/j.tet.2008.05.019
日期:2008.7
A study of the reactivity of Ph3PNLi towards phosphorus electrophiles allowed us to develop a general method to isolate, or cleanly generate in situ, a broad family of polyphosphinimines displaying PN–P bonds. A preliminary application of this methodology is presented here with the synthesis of various Schwesinger-type bases by a simple new procedure employing Ph3PNLi.
The reactions of α-ester phosphorusylids with several azides are described together with a kinetic investigation. The two reaction courses, leading either to diazo compounds or to vic-triazoles, are interpreted as proceeding by an addition elimination sequence. The low values of the entropies of activation provide evidence for a concerted addition in the first step of the reaction.