Ate Complexes in Iron-Catalyzed Cross-Coupling Reactions

作者：Parchomyk Tobias; Koszinowski Konrad

来源：Chemistry - A European Journal, 2016, 22(44): 15609-15613.

DOI：10.1002/chem.201603574

• cross coupling
• gas-phase reactions
• iron
• mass spectrometry
• reaction mechanisms

Iron-catalyzed cross-coupling reactions have an outstanding potential for sustainable organic synthesis, but remain poorly understood mechanistically. Here, we use electrospray-ionization (ESI) mass spectrometry to identify the ionic species formed in these reactions and characterize their reactivity. Transmetalation of Fe(acac)(3) (acac=acetylacetonato) with PhMgCl in THF (tetrahydrofuran) produces anionic iron ate complexes, whose nuclearity (1 to 4Fe centers) and oxidation states (ranging from -I to +III) crucially depend on the presence of additives or ligands. Upon addition of iPrCl, formation of the heteroleptic Fe-III complex [Ph3Fe(iPr)](-) is observed. Gas-phase fragmentation of this complex results in reductive elimination and release of the cross-coupling product with high selectivity.

• 出版日期2016-10-24