The synthesis of heteronuclear transition‐metal clusters derived from methylidyne tricobalt cluster precursors: The reaction of Mn(CO) with (μ 3 ‐CCl)Co 3 (CO) 7 (μ‐dppm). The crystal and molecular structure of (μ 3 ‐CH)Co 2 Mn(CO) 8 (μ‐dppm), a methylidyne cluster containing a seven‐coordinate manganese atom

The reaction of manganese pentacarbonyl anion with chloromethylidyne tricobaltnonacarbonyl, (μ 3 ‐CCl)Co 3 (CO) 9 , leads to reduction of the cluster with formation of Mn 2 (CO) 10 and Co(CO) , whilst reaction of Mn(CO) with the bis(diphenylphosphino)methane (dppm)‐stabilised cluster (μ 3 ‐CCl)Co 3 (CO) 7 (μ‐dppm) leads to the formation of (μ 3 ‐CH)Co 2 Mn(CO) 8 (μ‐dppm), 1. The unique feature of the structure of 1 is the incorporation of a seven‐coordinate manganese atom into the metal triangle.