Diphosphoryl-functionalized Polyoxometalates: Structurally and Electronically Tunable Hybrid Molecular Materials

Herein, we report the synthesis and characterization of a new class of hybrid Wells-Dawson polyoxometalate (POM) containing a diphosphoryl group (P2O6X) of the general formula [P2W17O57(P2O6X)](6-) (X=O, NH, or (CRR2)-R-1). Modifying the bridging unit X was found to impact the redox potentials of the POM. The ease with which a range of alpha-functionalized diphosphonic acids (X=(CRR2)-R-1) can be prepared provides possibilities to access diverse functionalized hybrid POMs. Compared to existing phosphonate hybrid Wells-Dawson POMs, diphosphoryl-substituted POMs offer a wider tunable redox window and enhanced hydrolytic stability. This study provides a basis for the rational design and synthesis of next-generation hybrid Wells-Dawson POMs.

Automated summary

Here, we report the synthesis and characterization of a new class of hybrid Wells-Dawson polyoxometalate (POM) with a diphosphoryl group (P2O6X). Modifying the bridging unit X impacts the redox potentials of the POM. The easy preparation of a range of alpha-functionalized diphosphonic acids (X=(CRR2)-R-1) provides possibilities for diverse functionalized hybrid POMs. Compared to existing phosphonate hybrid Wells-Dawson POMs, diphosphoryl-substituted POMs offer a wider tunable redox window and enhanced hydrolytic stability. This study provides a basis for the rational design and synthesis of next-generation hybrid Wells-Dawson POMs.