A neutral, acyclic, borataalkene-like ligand for group 11 metals: L- and Z-type ligands side by side

The overall neutral α-borylated phosphorus ylide Ph$_{3}$PC(Me)BEt$_{2}$ behaves like a polar borataalkene and can act as acyclic, ambiphilic π-type ligand with L- and Z-type functionalities side by side. In the complexes [MX{η$^{2}$-Ph$_{3}$PC(Me)BEt$_{2}$}] (M = Cu, (Ag), Au; X = Cl, NTf$_{2}$), the bonding is dominated by the highly nucleophilic ylidic carbon atom (L-type ligand). The Lewis acidic boron atom furnishes nonetheless a small but significant bonding contribution (Z-type ligand).