Multi-step and multi-component organometallic synthesis in one pot using orthogonal mechanochemical reactions†
We demonstrate that the mechanochemical strategies for oxidative addition and ligand substitution on organometallic centers can be mutually orthogonal, permitting the rational design of multi-component mechanochemical reaction procedures for assembling complex or solution-sensitive organometallic species from three, four or even five components in one pot. The herein established synthetic procedures represent a new level of complexity in mechanochemical reactions by milling and are the first to combine redox and ligand substitution reactions into mechanochemical strategies for either one-pot sequential (“telescoping”) or one-pot multi-component syntheses. This ability to combine mechanochemical transformations has enabled the solvent-free, room-temperature syntheses of relatively complex organometallics directly for simple zerovalent metal carbonyls as the simplest precursors. In particular, we demonstrate the efficiency of mechanochemical oxidative addition by targeting selected pentacarbonyl halides (fluoride, chloride, bromide, iodide) of rhenium(I) and manganese(I), and illustrate the potential of multi-step organometallic mechanochemistry in the syntheses of selected fac-tricarbonyl complexes of these metals.