Tris( tert ‐butylisonitrile)hexacarbonyl‐μ 3 ‐ethylidyne‐ triangulo ‐tricobalt(I)(3 Co—Co )

The title molecule, [Co 3 (C 2 H 3 )(C 5 H 9 N) 3 (CO) 6 ] or [Co 3 (μ 3 ‐CCH 3 )(CN t Bu) 3 (CO) 6 ], lies on a threefold rotation axis. The three isonitrile ligands each occupy an equatorial site on each of the three Co atoms. The average Co—Co bond length is 2.4769 (6) Å. The tert ‐butyl groups are disordered over two orientations, with site occupancies of ca 0.6:0.4.