Metathesis using Grubbs-type alkylidene complexes can be used to synthesize terminal carbido-containing complexes. One example is RuC(PCy)Cl with a Ru-C distance of 163 pm, typical for a triple bond. The complex can be obtained by metathesis of vinyl acetate to give [Ru(CH-p-CHMe)(PCy)Cl] results in a metastable Ru(Cl)(PCy)CHOAc complex, which eliminates acetic acid.
The "naked" carbido ligand is weakly basic, forming complexes with other metal centers. The C-M bond is typically found to be around 1.65 Å. The C NMR resonance values for the carbido carbons vary widely, but range from δ211-406. Another example of a terminal carbido complex is Li[MoC(NR2)3] (Mo-C distance of 172 pm), which forms upon deprotonation of the respective methylidyne precursor.