Ultrafine Sub-1 nm One-Dimensional Coordination Polymer Nanowires for Boosting Photocatalytic Functionalization of...

The heterogenization of molecular catalysts to be compatible with industrialization demands still faces great challenges. In this work, we demonstrate for the first time that the activity of a molecular catalyst is unrestricted when installed in nanostructured coordination polymers (CPs). CPs that can be used to obtain ultrafine nanowires by ultrasound exfoliation are extremely limited. We illustrate that chain-like CPs can be designed using electrostatic ligand-capped low-coordination-number metal ions and electropositive ligands as building blocks. This guides the preparation of the three-dimensional (3D) chain-like CPs from chloride ion-capped Cu-based chromophores and 1,1'-(1,4-phenylenebis(methylene))bis(3-carboxy quinolin-1-ium) chloride; subsequently, ultrafine sub-1 nm nanowires were obtained via ultrasound exfoliation. The formed ultrafine sub-1 nm CP nanowires demonstrate high activity enhancement for functionalization of C(sp³)-H bonds with conversion being significantly increased for alkylation, thiolation, and oxidation of C(sp³)-H bonds after exposure to external surfaces of the flexible nanowires. Therefore, the observed activity increases in the order CuCl₂ < bulk CP crystals < CP nanowires in functionalization of C(sp³)-H bonds. This work not only provides a strategy for constructing chain-like CPs and their ultrafine nanowires but also paves the way for expanding the diversity of the ultrafine 1D CP nanowires.