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DOE OSTI · 1985167

Single‐Crystal to Single‐Crystal Transformations: Stepwise CO 2 Insertions into Bridging Hydrides of [(NHC)CuH] 2 Complexes

Patrick, Evan A.·Bowden, Mark E.·Erickson, Jeremy D.·Bullock, R. Morris·Tran, Ba L.
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Abstract

Abstract Mechanistic studies of substrate insertion into dimeric [(NHC)CuH] 2 (NHC=N‐heterocyclic carbene) complexes with two bridging hydrides have been shown to require dimer dissociation to generate transient, highly reactive (NHC)Cu−H monomers in solution. Using single‐crystal to single‐crystal (SC‐SC) transformations, we discovered a new pathway of stepwise insertion of CO 2 into [(NHC)CuH] 2 without complete dissociation of the dimer. The first CO 2 insertion into dimeric [(IPr*OMe)CuH] 2 (IPr*OMe=N,N′‐bis(2,6‐bis(diphenylmethyl)‐4‐methoxy‐phenyl)imidazole‐2‐ylidene) produced a dicopper formate hydride [(IPr*OMe)Cu] 2 (μ‐1,3‐O 2 CH)(μ‐H). A second CO 2 insertion produced a dicopper bis(formate), [(IPr*OMe)Cu] 2 (μ‐1,3‐O 2 CH)(μ‐1,1‐O 2 CH), containing two different bonding modes of the bridging formate. These dicopper formate complexes are inaccessible from solution reactions since the dicopper core cleanly ruptures to monomeric complexes when dissolved in a solvent.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCO2 reductionCu formateCu hydrideN-heterocyclic carbenessingle crystal transformation

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Patrick, Evan A., Bowden, Mark E., Erickson, Jeremy D., Bullock, R. Morris, Tran, Ba L.. 2023-06-15. Single‐Crystal to Single‐Crystal Transformations: Stepwise CO 2 Insertions into Bridging Hydrides of [(NHC)CuH] 2 Complexes. https://doi.org/10.1002/anie.202304648

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