Topology‐Templated Synthesis of Crystalline Porous Covalent Organic Frameworks

A strategy is presented for the synthesis of crystalline porous covalent organic frameworks via topology‐templated polymerization. The template is based on imine‐linked frameworks and their (001) facets seed the C=C bond formation reaction to constitute 2D sp2 carbon‐conjugated frameworks. This strategy is applicable to templates with different topologies, enables designed synthesis of frameworks that cannot be prepared via direct polymerization, and creates a series of sp2 carbon frameworks with tetragonal, hexagonal, and kagome topologies. The sp2 carbon frameworks are highly luminescent even in the solid state and exhibit topology‐dependent π transmission and exciton migration; these key fundamental π functions are unique to sp2 carbon‐conjugated frameworks and cannot be accessible by imine‐linked frameworks, amorphous analogues, and 1D conjugated polymers. These results demonstrate an unprecedented strategy for structural and functional designs of covalent organic frameworks. Attract to plant lattice growth: Imine‐linked covalent organic frameworks (blue) attract organic building blocks on a 2D x−y surface and model C=C bond formation to create 2D sp2 carbon lattices with different topologies (yellow). Frameworks are thus formed that cannot be produced by direct polymerization. The synthesis of such lattices leads to knowledge about π transmission and exciton migration across the 2D lattice.