Figure 1.

Illustration of the mechanism of adatom‐mediated cyclodehydrogenation on Au(111). Dehydrogenation is induced by a thermally generated adatom, followed by adatom‐mediated C−C bond formation. The cyclodehydrogenation is finalized by a tautomerization step and subsequent dehydrogenation for which the adatom does not participate. In the dehydrogenation and tautomerization steps, the paths of the involved hydrogen atoms are indicated by red arrow. The colors of the different atom types are indicated at the bottom of the figure.