Visualizing the Product of a Formal Cycloaddition of 7,7,8,8-Tetracyano-p-quinodimethane (TCNQ) to an Acetylene-Appended Porphyrin by Scanning Tunneling Microscopy on Au(111)

Click it: The applicability of a formal [2+2] cycloaddition between electron‐rich alkynes and electron‐deficient TCNQ on an atomically clean Au(111) surface was demonstrated by scanning tunneling microscopy (STM) and X‐ray photoelectron spectroscopy (XPS). At low coverage, monomeric and self‐assembled dimeric species of the initial compounds as well as of the reaction product, a TCNQ‐conjugated porphyrin, could be visualized.