Construction of 2,2′:6′,2′′-terpyridine-modified porous organic polymers <i>via</i> building unit engineering: preferred and universal transition metal carrier and catalytic application

Porous organic polymers (POPs) serve a key function as transition metal carriers and have attracted widespread attention in the catalysis field. However, a preferred and universal transition metal carrier remains elusive. In this study, we designed and synthesized a preferred 2,2':6',2''-terpyridine-containing building motif and prepared a POP (POP-Tpy-1) <i>via</i> the Buchwald-Hartwig coupling reaction of a diamino-linker and trisbromo-node. Taking full advantage of the strong bonding ability of the terpyridine moiety and the availability of binding room, coupled with the high stability of the POP itself, POP-Tpy-1 displayed universal coordination binding and a high load capacity for many common transition metals (Mn²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Ru³⁺, Pd²⁺, Fe²⁺, and Cu⁺). The corresponding metal-loaded porous organic polymers (POP-Tpy-1-M) can serve as transition metal heterogeneous catalysts, and these were conceptually verified by typical synthesis reactions, including cross-dehydrogenative coupling, click reactions, and Suzuki-Miyaura coupling reactions.