Bis(imino)phosphanes: Synthesis and Coordination Chemistry

Bis­(imino)­phosphanes can be synthesized efficiently from iminophosphanes and nitrilium triflates, allowing for nonsymmetric substitution at the imine groups. Symmetrically substituted derivatives can even be obtained in a one-pot procedure from primary phosphanes. These potential N,N-bidentate ligands are sensitive toward Cu­(II), Zn­(II), and rhodium­(I) sources, resulting in loss of an imine group. For [RhCl­(COD)]2 this led to an N,P- and P-chelating bimetallic complex. Bis­(imino)­phosphanes with C-Me substituents rearrange in situ to unique 1,3,5-phosphadiazapentadienes for which a P-coordinated gold­(I) complex is reported. The bis­(imino)­phosphanes are readily oxidized to stable bis­(imino)­phosphane oxides with aqueous H2O2.