Mechanochemical Synthesis of [Rh(L)(acac)(CO] Complexes (L = N-Heterocyclic Carbene or Phosphine)

Abstract

The mechanochemical synthesis of well-defined [Rh(L)(acac)(CO)] (L = NHC or phosphine) complexes via planetary milling and manual grinding with a mortar and pestle is reported. This solventless protocol, which proceeds via a ligand displacement from [Rh(acac)(CO)2], was successfully applied to various NHC·HCl salts (NHC = IPr, SIPr, IMes, SIMes, IPr*), neat phosphines (PPh3 and PCy3), and the PtBu3·HBF4 salt. This method offers rapid access, using readily available tools, to the electronic characterization of ligands in organometallic chemistry.