Phospha-scorpionate complexes by click chemistry using phenyl azide and ethynylphosphine oxides

The copper-catalyzed Click reaction of phenyl azide with ethynylphosphine oxides provides new P-substituted triazoles. With tris(ethynyl)phosphine oxide this route affords a versatile scorpionate ligand that coordinates to RhCl3 as a tripodal N ligand. Upon reduction, the same ligand can act as a P donor to W(CO)(5). Both coordination modes can be combined, giving access to a bimetallic Mo/W complex.