Despite significant progress in recent years, the cleavage of unstrained C(sp(3))-C(sp(3)) bonds remains challenging. A C-C coupling and cleavage reaction in a PC(sp(3))P iridium pincer complex is mechanistically studied; the reaction proceeds via the formation of a carbene intermediate and can be described as a competition between α-hydrogen and α-alkyl elimination; the latter process was observed experimentally and is an unusual way of C(sp(3))-C(sp(3)) bond scission, which has previously not been studied in detail. Mechanistic details that are based upon kinetic studies, activation parameters, and DFT calculations are also discussed. A full characterization of a C-C agostic intermediate is presented.
Keywords: density functional calculations; elimination; iridium; kinetics; pincer complexes.
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