Isomerization reaction characteristic equation

Even under the most inert atmosphere conditions, the 31CP/MAS spectrum of the immobilized ligand showed a major signal at 6 = 42 ppm (wrt 85% H3POO characteristic of phosphine oxide rather than phosphine. This could be quantitatively reduced by HSiCl3 and this surface reaction monitored by NMR but the subsequent exchange reaction (equation [5]) generated substantial quantities of phosphine oxide and a number of different isomeric complexes were f ormed. 

In order to define the stereochemical characteristics of the cyclopentene forming reaction, the thermal isomerization of optically pure (-f)( 15,25)-rruns,rrans-2-methyl-l-propenylcyclopropane (205) has been investigated (equation 138). 

Organozirconates. Zwitterionic zirconocene-ate see Ate Complexes intermediates have been evoked to explain some reaction mechanisms (see Section 2.3.3). In fact, electron transfer from an organic ligand to 16-electron metal center permits the generation of a carbocationic center which can, then, undergoes isomerization and rearrangement characteristic of carbocations. It is now possible to isolate and characterize stable zwitterionic phosphonium zirconate complexes (equation 18). ... 

---