Group 14 Substituted Carbyne ComplexesAn Almost Complete Set: [Mo(CAPh₃)(CO)₂(Tp*)] (Tp* = Hydrotris(dimethylpyrazolyl)borate; A = Si, Ge, Sn, Pb but A ≠ C)

The successive reactions of [Mo(CBr)(CO)2(Tp*)] (Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate) with nBuLi and ClAPh3 (A = Ge, Sn, Pb) afford the carbyne complexes [Mo(CAPh3)(CO)2(Tp*)] but fail in the case of ClCPh3 and ClSiPh3. The silicon analogue [Mo(CSiPh3)(CO)2(Tp*)] may, however, be obtained via a multistep Fischer−Mayr synthesis. [Mo(CPbPh3)(CO)2(Tp*)] is the first example of a plumbyl alkylidyne complex.