Electrochemical Properties of Ru Polypyridyl Phosphonates

[Ru(bpyPO(3)H(2))(bpy)Cl]Cl (bpyPO(3)H(2)=6,6'-bipyridin-2-yl)phosphonic acid) and [Ru(tpy)(MepyPO(3)H(2))Cl]Cl (MepyPO(3)H(2)=(pyridin-2-ylmethyl)phosphonic acid) were synthesized and characterized spectroscopically and electrochemically. Each compound was found to exhibit proton-coupled electron transfer (PCET). In the case of [Ru(bpyPO(3)H(2))(bpy)Cl]Cl, a Ru(V/IV) couple was detected at 1.4 V vs. NHE. Each complex was tested for its ability to catalyze C-H bond oxidation using a variety of sacrificial oxidants, and it was found that under aqueous conditions [Ru(bpyPO(3)H(2))(bpy)Cl]Cl oxidizes secondary C-H bonds using sodium periodate (NaIO4) as the primary oxidant.

Automated summary

Two phosphorus-containing ruthenium complexes were synthesized and characterized spectroscopically and electrochemically. Both complexes exhibited proton-coupled electron transfer (PCET) behavior. A Ru(V/IV) couple was detected at 1.4 V vs. NHE for [Ru(bpyPO(3)H(2))(bpy)Cl]Cl. The complexes were tested for their ability to catalyze C-H bond oxidation and it was found that [Ru(bpyPO(3)H(2))(bpy)Cl]Cl can oxidize secondary C-H bonds using NaIO4 as the primary oxidant under aqueous conditions.