[η-(Phenyl-ethyn-yl)cyclo-penta-dien-yl](η-tetra-phenyl-cyclo-butadiene)cobalt(I).

In the title compound, [Co(C(13)H(9))(C(28)H(20))], the Co atom is sandwiched between cyclo-penta-dienyl and cyclo-butadienyl rings that are inclined at a dihedral angle of 2.6 (3)°. The four phenyl rings are tilted with respect to the cyclo-butadienyl plane so that the C(4)Ph(4) unit constitutes a four-bladed propeller. The phenyl ring of the phenyl-alkyne substituent is inclined to the cyclo-penta-dienyl ring at an angle of 34.92 (18)°. The crystal structure is stabilized solely by C-H⋯π inter-actions which generate a three-dimensional network.

(Carbonyl-1κC)bis-[2,3(η)-cyclo-penta-dien-yl][µ(3)-(S-methyl trithio-carbonato)methylidyne-1:2:3κC,S'':C:C](triphenyl-phosphine-1κP)(µ(3)-sulfido-1:2:3κS)dicobalt(II)iron(II) trifluoro-methane-sulfonate.

The asymmetric unit of the title compound, [FeCo(2)(C(5)H(5))(2)(C(3)H(3)S(3))S(C(18)H(15)P)(CO)]CF(3)SO(3), consists of a triangular irondicobalt cluster cation and a trifluoro-methane-sulfonate anion. In the cation, the FeCo(2) triangle is symmetrically capped on one face by an S atom and on the other by a C atom linked to a methyl trithio-carbonate residue that bridges the Fe-C bond. Each Co atom carries a cyclo-penta-dienyl ligand while the Fe atom coordinates to one carbonyl and one triphenyl-phosphine ligand. In the crystal structure, the cation is linked to the anion by a number of weak non-classical C-H⋯O and C-H⋯F hydrogen bonds and weak S⋯O (3.317 Å) and S⋯F (3.198 Å) inter-actions. The structure is further stabilized by additional inter-molecular C-H⋯O, C-H⋯F and O⋯O (2.942 Å) contacts, together with an unusual S⋯π(Cp) inter-action (S⋯centroid distance = 3.385 Å), generating an extended network.