On‐Surface Synthesis of Porphyrin‐Complex Multi‐Block Co‐Oligomers by Defluorinative Coupling

On‐surface chemical reaction has become a very powerful technique to synthesize nanostructures by linking small molecules in the bottom‐up approach. Given the fact that most reactants are simultaneously activated at certain temperatures, a sequential reaction in a controlled way has remained challenging. Here, we present an on‐surface synthesis of multi‐block co‐oligomers from trifluoromethyl (CF 3 ) substituted porphyrin metal complexes. The oligomerization on Au(111) is demonstrated with a combination of bond‐resolved scanning probe microscopy and density functional theory (DFT) calculations. Even after the first oligomerization of single monomer unit, the termini of the oligomer keep the CF 3 group, which can be used as a reactant for further coupling in a sequential order. Consequently, copper, cobalt, and palladium complexes of bisanthracene‐fused porphyrin oligomers were linked with each other in a designed order.