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[Rh2(MEPY)4] is a versatile catalyst for asymmetric synthesis but its preparation requires purification by chromatography on surface‐modified silica. A higher yielding procedure based on a more convenient work‐up is presented herein. Moreover, a much improved method for the preparation of [BiRh(OTfa)4] is described, which makes this heterobimetallic complex readily available. Subsequent exchange of the trifluoroacetate ligands opens access to a so far underappreciated family of (chiral) paddlewheel complexes. While [BiRh] complexes comprising four carboxylate ligands are highly adequate for intermolecular asymmetric cyclopropanation reactions, [BiRh(MEPY)4] as the heterobimetallic cousin of [Rh2(MEPY)4] was found to be surprisingly unreactive; DFT calculations uncover the reasons for this inertia. [ABSTRACT FROM AUTHOR]

The synthesis of the Cu-borate complexes [(6Mes)Cu(HBR3)] featuring the unusual [HBEt3]− ( 5) and [HB(C6F5)3]− ( 6) ligands is described. Experimental and computational studies show both compounds feature a direct Cu-H interaction, but that while 5 is two-coordinate, 6 displays an additional, stabilizing Cu-Cipso(C6F5) interaction. [ABSTRACT FROM AUTHOR]

The synthesis of the Cu-borate complexes [(6Mes)Cu(HBR3)] featuring the unusual [HBEt3]− ( 5) and [HB(C6F5)3]− ( 6) ligands is described. Experimental and computational studies show both compounds feature a direct Cu-H interaction, but that while 5 is two-coordinate, 6 displays an additional, stabilizing Cu-Cipso(C6F5) interaction. [ABSTRACT FROM AUTHOR]

The synthesis of the Cu-borate complexes [(6Mes)Cu(HBR3)] featuring the unusual [HBEt3]− ( 5) and [HB(C6F5)3]− ( 6) ligands is described. Experimental and computational studies show both compounds feature a direct Cu-H interaction, but that while 5 is two-coordinate, 6 displays an additional, stabilizing Cu-Cipso(C6F5) interaction. [ABSTRACT FROM AUTHOR]

The synthesis of the Cu-borate complexes [(6Mes)Cu(HBR3)] featuring the unusual [HBEt3]− ( 5) and [HB(C6F5)3]− ( 6) ligands is described. Experimental and computational studies show both compounds feature a direct Cu-H interaction, but that while 5 is two-coordinate, 6 displays an additional, stabilizing Cu-Cipso(C6F5) interaction. [ABSTRACT FROM AUTHOR]

The electrophilic character of free diamidocarbenes (DACs) allows them to activate inert bonds in small molecules, such as NH3 and P4. Herein, we report that metal coordinated DACs also exhibit electrophilic reactivity, undergoing attack by Zn and Cd dialkyl precursors to afford the migratory insertion products [(6-MesDAC-R)MR] (M=Zn, Cd; R=Et, Me; Mes=mesityl). These species were formed via the spectroscopically characterised intermediates [(6-MesDAC)MR2], exhibiting barriers to migratory insertion which increase in the order MR2 = ZnEt2 < ZnMe2 < CdMe2. Compound [(6-MesDAC-Me)CdMe] showed limited stability, undergoing deposition of Cd metal, by an apparent β-H elimination pathway. These results raise doubts about the suitability of diamidocarbenes as ligands in catalytic reactions involving metal species bearing nucleophilic ligands (M-R, M-H). [ABSTRACT FROM AUTHOR]