The synthesis of a threefold symmetric nanographene with 19 cata‐fused benzene rings distributed within six branches is reported. This flat dendritic starphene, which is the largest unsubstituted cata‐condensed PAH that has been obtained to date, was prepared in solution by means of a palladium‐catalyzed aryne cyclotrimerization reaction and it was characterized on surface by scanning probe microscopy
Structurally diverse macrocyclic pyridones can be efficiently synthesized by a rhodium(III)-catalyzedC–Hactivation/heterocyclization of ω-alkynyl α-substituted acrylic hydroxamates. The use of a O-pivaloyl hydroxamate as directing group was crucial to achieve efficient catalyst turnover in a redox-neutral process.