  Organometallic compounds constitute a very large group of substances that
contain at least one metal-to-carbon bond in which the carbon is part of an
organic group. They have played a major role in the development of the science
of chemistry. These compounds are used to a large extent as catalysts
(substances that increase the rate of reactions without themselves being
consumed) and as intermediates in the laboratory and in industry. Recently,
novel quantum phenormena such as topological insulators and superconductors
were also suggested in these materials. However, there has been no report on
the experimental exploration for the topological state. Evidence for
superconductivity from the zero-resistivity state in any organometallic
compound has not been achieved yet, though much efforts have been devoted. Here
we report the experimental realization of superconductivity with the critical
temperature of 3.6 K in a potassium-doped organometallic compound, $ i.e.$
tri-$o$-tolylbismuthine with the evidence of both the Meissner effect and the
zero-resistivity state through the $dc$ and $ac$ magnetic susceptibility and
resistivity measurements. The obtained superconducting parameters classify this
compound as a type-II superconductor. The benzene ring is identified to be the
essential superconducting unit in such a phenyl organometallic compound. The
superconducting phase and its composition are determined by the combined
studies of the X-ray diffraction and theoretical calculations as well as the
Raman spectroscopy measurements. These findings enrich the applications of
organometallic compounds in superconductivity and add a new electron-acceptor
family for organic superconductors. This work also points to a large pool for
finding superconductors from organometallic compounds.
