Encapsulated Bimetallic Complexes Based on Earth-abundant Metals for (Photo)Catalysis – CuBicBeam

Metal complexes have emerged as effective tools to promote light-induced chemical transformations. Homogeneous photocatalysis has been dominated by rare metals such as Ru and Ir which, with the appropriate ligands, strongly absorb visible light, an indispensable property for harnessing solar energy as a renewable energy source to develop sustainable processes in chemistry. Recently, however, the development of photoactivatable complexes with Earth-abundant metals has attracted increasing attention and copper has emerged as a promising alternative to precious metals. Copper complexes have certain structural advantages but globally exhibit low photoactivity in the visible range.
The innovative nature of the CuBicBeam project consists of exploiting a supramolecular cyclodextrin (CD) platform comprising a cavity to introduce Cu(I) by encapsulation and promote the construction of bimetallic complexes by associating Cu(I) with a second abundant metal and appropriate ligands to increase the photoactivity under visible light exposure.
Examples of photoactivatable bimetallic complexes are very rare, and those based on Earth-abundant metals with metallophillic interactions have not been explored. The Sorbonne group (P1 France) has already shown that the encapsulation of Cu(I) in CDs induces particular cavity-dependent catalytic properties and has launched a program for the design of Cu-based photoactivatable complexes. The Mankad group (P2 USA) is very experienced in bimetallic complexes with Cu and has developed advanced techniques (resonant X-ray diffraction and charge density measurements) to analyze their structure. The two groups will work in synergy to design, synthesize and analyze the structures/properties of bimetallic complexes with the aim of improving photocatalytic systems using abundant metals and visible light.