Ligand‐Mediated Microenvironment in COFs Incorporating Ion‐Pair Motifs and Atomically Dispersed Copper Sites for Cascade CO 2 Conversion

Precisely programming the local microenvironment of covalent organic frameworks (COFs) is critical for catalytic selectivity, but remains challenging, especially via de novo synthesis. Here, we present a rational ligand‐effect‐oriented microenvironment design for the de novo construction of multifunctional COFs that integrate N + /Br − ion‐pairs and imine‐anchored atomically dispersed copper sites. A key innovation lies in the precise control of the COFs microenvironment, enabling a seamless three‐component cascade reaction of CO 2 (1 bar), epoxides, and anilines to afford 2‐oxazolidinones under mild and precious‐metal‐free conditions. The optimized catalyst, Cu@PD‐iCOF, delivers up to 99% yield, exhibits broad functional‐group compatibility, and retains >96% activity over nine cycles. This work shows that combining ion‐pairs and single‐atom sites reprograms the COFs microenvironment for efficient CO 2 utilization.