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We report the selective electrochemical biphasic capture of the uranyl cation (UO 2 2+ ) from mixed-metal alkali (Cs + ), lanthanide (Nd 3+ , Sm 3+ ), and actinide (Th 4+ , UO 2 2+ ) aqueous solutions to an organic, 1,2-dichloroethane (DCE), phase using the ortho -substituted nido -carborane anion, [1,2-(Ph 2 PO) 2 -1,2-C 2 B 10 H 10 ] 2− (POCb2−). The reduced POCb2− is generated by electrochemical reduction of the closo -carborane, POCb, prior to mixing with the aqueous mixed-metal solution. Subsequent UO 2 2+ release from the captured product, [UO2(POCb)2]2−, was performed by galvanostatic bulk electrolysis of the DCE phase and back-extraction of UO 2 2+ to a fresh aqueous phase. The selective capture and release of UO 2 2+ was confirmed by combined ICP-OES and NMR spectral analyses of the aqueous and organic phases, respectively, against the newly synthesized nido -carborane complexes, [[CoCp*2][Cs(POCb)]]2, [CoCp*2]3[Nd(POCb)3], [CoCp*2]3[Sm(POCb)3], and [CoCp*2]2[Th(POCb)3]. 

We report the facile activation of aryl E–H (ArEH; E = N, O, S; Ar = Ph or C 6 F 5 ) or ammonia N–H bonds via coordination-induced bond weakening to a redox-active boron center in the complex, (1 − ). Substantial decreases in E–H bond dissociation free energies (BDFEs) are observed upon substrate coordination, enabling subsequent facile proton-coupled electron transfer (PCET). A drop of >50 kcal mol −1 in H 2 N–H BDFE upon coordination was experimentally determined. 

We report the facile and efficient synthesis of common electrophilic haloboranes via a protonolysis reaction between Piers’ borane, HB(C₆F₅)₂, and H−X (X=Cl, Br). This route benefits from fast reaction times, easy setup, and minimal workup to yield the analytically pure etherates, (C₆F₅)₂BCl(OEt₂) (1) and (C₆F₅)₂BBr(OEt₂) (2), as well as the ether‐free tri‐coordinate species, (C₆F₅)₂BBr (3).

 

A magnesium hydride cation [(L)MgH] + supported by a macrocyclic ligand (L = Me 4 TACD; 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane) has been prepared by partial protonolysis of a mixed amide hydride [(L)MgH 2 Mg{N(SiMe 3 ) 2 } 2 ] and shown to undergo a variety of reactions with unsaturated substrates, including pyridine.