The reaction leading to the formation of the imine probably proceeds via nucleophilic addition to the heteroatom, creating a highly stabilized cyclopentadienyl anion. The intermediate anion then undergoes elimination of the tosylate. The only significant side reaction appears to be reduction of the imine tosylate to the unsubstituted imine (vide infra). One possible means of eliminating this problem may be substituting a different carbanion ...
![(3aR,7aR)-2-ethyl-[3a,4,5,6,7,7a-octahydro-1,3-dimethyl-1,3,2-benzodiazaphosphole]-2-oxide Structure](https://image.chemsrc.com/caspic/001/91633-73-7.png)
