Synthesis, Structure, and Bonding of the Cation [{(C6H5)3PAu}5C]

An AuC bond order of 0.8 characterizes the pentaauriomethyl cation 1, so that the central carbon atom cannot be regarded as hypervalent. Compound 1 is formed from CH2[B(OMe)2]2 and [Ph3PAuCl] in the presence of CsF as BF 4⊖ salt in 84% yield. The trigonal‐bipyramidal coordination of the carbon center is slightly distorted. This may be due to a reduction in energy upon lowering the symmetry or to ligand–ligand repulsion or packing effects.