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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]

In this essay I develop a case for games as a primitive form of culture and an early arrival at our ancestors' cultural gates. I analyze the modest intellectual prerequisites for game behavior including the use of metaphor, a reliance on constitutive rules, and an ability to understand the logic of entailment. In arguing for its early arrival during the late Middle and Upper Paleolithic, I develop a case for its powerful adaptive qualities in terms of both natural and sexual selection. I accept ecological dominance coupled with an increasing sense of self as primary sources of selection pressure. I show how these two factors threatened homeostatic balances ranging from low arousal and atrophy to malaise, depression, and anomie. I suggest that an antidote or adaptation was found in culturally-enhanced forms of play -- that is, formal, rule-governed games. The upshot of this analysis is a broadened discussion of cultural adaptation from one that often focuses on cooperation, social complexity, and language to other fundamental issues related to survival -- namely, increased leisure time, enhanced arousal needs, and the health and physical skills required for a hunter-forager existence. [ABSTRACT FROM AUTHOR]