PNP Ligands in Cobalt‐Mediated Activation and Functionalization of White Phosphorus

Transition‐metal mediated white phosphorus activation is of high interest as an ecological alternative to P4 chlorination pathway to the practically useful phosphorus products. Herein, we report a facile approach for P4 activation, transformation and subsequent functionalization using cobalt complexes bearing PNP ligands. The use of N,N‐bis(diphenylphosphino)amine as a ligand allows one to transform P4 tetrahedron into a zig‐zag chain with the formation of complex [Co(Ph2PNHP(Ph2)PPPPP(Ph2)NHPPh2)]BF4 (4). The presence of organic substituent at nitrogen atom in PNP ligand enables one to obtain complexes with η1‐coordinated P4 molecule, which indicates a crucial role of N−H bond in transformation of white phosphorus tetrahedron. Additionally, complex 4 can readily be functionalized by means of the reaction with Ph2PCl leading to the formation of a new complex bearing unique P9‐ligand. The obtained results provide opportunities for facile construction of new polyphosphorus ligands in the coordination sphere of transition metal complexes. White phosphorus (P4) can be activated in the coordination sphere of cobalt complexes bearing PNP ligands. The use of N,N bis(diphenylphosphino)amine as a ligand gives a P4 transformation into a zig‐zag chain which can readily be functionalized by Ph2P groups to form a complex containing a unique P9‐ligand. The presence of an organic substituent at the nitrogen atom in the PNP ligand gives complexes with an η1‐coordinated P4 molecule.