Reactivity of Methyl Groups in Actinide Metallocene Amidinate and Triazenido Complexes with Silver and Copper Salts

Abstract

The effect of the heteroleptic ligand sets {(C5Me5)2[iPrNC(Me)NiPr]}3− and {(C5Me5)2[(Me)NNN(Ad)]}3− on actinide−carbon bond reactivity has been evaluated by examining the monomethyl actinide metallocene amidinate complexes (C5Me5)2[iPrNC(Me)NiPr-κ2N,N′]AnMe (An = U, 1; Th, 2) and the triazenido complex (C5Me5)2[(Me)NNN(Ad)-κ2N1,3]UMe, 3. This has led to a facile method to convert methyl groups in U4+ and Th4+ complexes to halide and pseudo-halide ligands. Complexes 1 and 3 react with AgOSO2CF3 (AgOTf) to produce (C5Me5)2[iPrNC(Me)NiPr-κ2N,N′]U(OTf), 4, and (C5Me5)2[(Me)NNN(Ad)-κ2N1,3]U(OTf), 5, respectively. The methyl complexes are also reactive with copper reagents, as demonstrated by the reactions of CuI with 1 and 2 to make (C5Me5)2[iPrNC(Me)NiPr-κ2N,N′]UI, 6, and (C5Me5)2[iPrNC(Me)NiPr-κ2N,N′]ThI, 7, respectively. Similarly, reactions of CuBr with 1 and 3 generate (C5Me5)2[iPrNC(Me)NiPr-κ2N,N′]UBr, 8, and (C5Me5)2[(Me)NNN(Ad)-κ2N1,3]UBr, 9, respectively. These triflate and halide complexes are good ...