Supramolecular Template-Assisted Catalytic [2+2] Photocycloaddition in Homogeneous Solution

Supramolecular interactions can help recognize and organize substrates around an enzyme's active sites and subsequently assemble a new molecule in a certain way. Inspired by nature's control of reactions, in this work we designed a template catalyst equipped with ditopicAu(I)-N-heterocyclic carbene (NHC) functional sites that direct olefin substrates into reactive geometries via collaboration of coordination-driven interactions. Notably, this catalyst enables the realization of catalytic [2+2] photocycloadditionswith as low as 2 mol % catalyst loading in homogeneous solution and the delivery of a series of cyclobutane derivatives with excellent conversions and stereoselectivities. The success of gram-scale reactions further demonstrates the feasibility of this strategy, which lays a solid foundation for the large-scale preparation of cyclobutane derivatives in the future. [GRAPHICS] .