“…Herein we report how we synthesized the [Ru=C=CHR] unit by acetylene rearrangements2, 6 in the reaction with 1 (see Scheme ), and how we then converted the [Ru=C=CHR] unit into a variety of carbene and metallacumulene structures 2, 6. The paper most related to our work reports the reaction of Ru–porphyrin with ethyne to produce a μ ‐biscarbene 7. Although these functionalities have various precedents in the case of cyclopentadienyl, phosphine, arene,2, 6, 8 and some amine9 ligands, they are absent in the macrocyclic ruthenium chemistry.…”