Cp3Zr(acetonitrile)(+): Structure of an electron-rich organometallic d(0)-cation

The organometallic salt [Cp3Zr(N drop C-CH3)](+) [CH3B-(C6F5)(3)](-) (3a) has been prepared by treatment of Cp3ZrCH3 with B(C6F5)(3) followed by the addition of acetonitrile. X-ray crystal structure analysis of 3a shows that it cation consists of three uniformly coordinated eta(5)-cyclopentadienyl ligands about the zirconium atom. The acetonitrile ligand is end-on coordinated. In the linear [Zr]-N drop C-CH3 unit the C drop N triple bond [N-C2 1.126(5) Angstrom] is slightly shorter than in the free acetonitrile molecule [d(C drop N)=1.141(2) Angstrom], the structure of which was determined as a reference by X-ray diffraction of a crystal obtained by IR-laser-induced zone melting on the diffractometer.