Sol-Gel Heterogeneization of an Ir(III) Complex for Sustainable Visible-Light Redox Photocatalysis.

Photocatalysis is a key strategy for the development of sustainable solar-driven chemical processes. In this work, we report the synthesis and characterization of a novel organometallo-ionosilica material derived from the self-condensation of an alcoxysilane functionalized Ir(III) complex. In acetonitrile suspension, the material retains the photophysical properties of its precursor in solution in the same solvent, together with a significant absorption in the visible between 400 and 500 nm. As a heterogeneous photocatalyst, the material showed high efficiency in the reductive dehalogenation of 2-bromoacetophenone under blue light irradiation, achieving high yields of conversion of about 90%, and excellent recyclability in seven catalytic cycles, retaining more than 70% of the catalytic efficiency. All these properties of the self-condensed material highlight its potential as an efficient and sustainable heterogeneous photocatalyst for applications in organic synthesis and solar-driven redox processes.