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The complexes Ag(L)n[WCA] (L=P4S3, P4Se3, As4S3, and As4S4; [WCA]=[Al(ORF)4]− and [F{Al(ORF)3}2]−; RF=C(CF3)3; WCA=weakly coordinating anion) were tested for their performance as ligand‐transfer reagents to transfer the poorly soluble nortricyclane cages P4S3, P4Se3, and As4S3 as well as realgar As4S4 to different transition‐metal fragments. As4S4 and As4S3 with the poorest solubility did not yield complexes. However, the more soluble silver‐coordinated P4S3 and P4Se3 cages were transferred to the electron‐poor Fp+ moiety ([CpFe(CO)2]+). Thus, reaction of the silver salt in the presence of the ligand with Fp−Br yielded [Fp−P4S3][Al(ORF)4] (1 a), [Fp−P4S3][F(Al(ORF)3)2] (1 b), and [Fp−P4Se3][Al(ORF)4] (2). Reactions with P4S3 also yielded [FpPPh3−P4S3][Al(ORF)4] (3), a complex with the more electron‐rich monophosphine‐substituted Fp+ analogue [FpPPh3]+ ([CpFe(PPh3)(CO)]+). All complex salts were characterized by single‐crystal XRD, NMR, Raman, and IR spectroscopy. Interestingly, they show characteristic blueshifts of the vibrational modes of the cage, as well as structural contractions of the cages upon coordination to the Fp/FpPPh3 moieties, which oppose the typically observed cage expansions that lead to redshifts in the spectra. Structure, bonding, and thermodynamics were investigated by DFT calculations, which support the observed cage contractions. Its reason is assigned to σ and π donation from the slightly P−P and P−E antibonding P4E3‐cage HOMO (e symmetry) to the metal acceptor fragment. [ABSTRACT FROM AUTHOR]

The complexes Ag(L)n[WCA] (L=P4S3, P4Se3, As4S3, and As4S4; [WCA]=[Al(ORF)4]− and [F{Al(ORF)3}2]−; RF=C(CF3)3; WCA=weakly coordinating anion) were tested for their performance as ligand‐transfer reagents to transfer the poorly soluble nortricyclane cages P4S3, P4Se3, and As4S3 as well as realgar As4S4 to different transition‐metal fragments. As4S4 and As4S3 with the poorest solubility did not yield complexes. However, the more soluble silver‐coordinated P4S3 and P4Se3 cages were transferred to the electron‐poor Fp+ moiety ([CpFe(CO)2]+). Thus, reaction of the silver salt in the presence of the ligand with Fp−Br yielded [Fp−P4S3][Al(ORF)4] (1 a), [Fp−P4S3][F(Al(ORF)3)2] (1 b), and [Fp−P4Se3][Al(ORF)4] (2). Reactions with P4S3 also yielded [FpPPh3−P4S3][Al(ORF)4] (3), a complex with the more electron‐rich monophosphine‐substituted Fp+ analogue [FpPPh3]+ ([CpFe(PPh3)(CO)]+). All complex salts were characterized by single‐crystal XRD, NMR, Raman, and IR spectroscopy. Interestingly, they show characteristic blueshifts of the vibrational modes of the cage, as well as structural contractions of the cages upon coordination to the Fp/FpPPh3 moieties, which oppose the typically observed cage expansions that lead to redshifts in the spectra. Structure, bonding, and thermodynamics were investigated by DFT calculations, which support the observed cage contractions. Its reason is assigned to σ and π donation from the slightly P−P and P−E antibonding P4E3‐cage HOMO (e symmetry) to the metal acceptor fragment. [ABSTRACT FROM AUTHOR]

The recently published purely metallo-organic NiI salt [Ni(cod)2][Al(ORF)4] (1, cod=1,5-cyclooctadiene, RF= C(CF3)3) provides a starting point for a new synthesis strategy leading to NiI phosphine complexes, replacing cod ligands by phosphines. Clearly visible colour changes indicate reactions within minutes, while quantum chemical calculations (PBE0-D3(BJ)/def2-TZVPP) approve exergonic reaction enthalpies in all performed ligand exchange reactions. Hence, [Ni(dppp)2][Al(ORF)4] (2, dppp=1,3-bis(diphenylphosphino) propane), [Ni(dppe)2][Al(ORF)4] (3, dppe=1,3-bis(diphenyl- phosphino)ethane), three-coordinate [Ni(PPh3)3] [Al(ORF)4] (4) and a remarkable two-coordinate NiI phosphine complex [Ni(PtBu3)2][Al(ORF)4] (5) were characterised by single crystal X-ray structure analysis. EPR studies were performed, confirming a nickel d9 -configuration in complexes 2, 4 and 5. This result is supported by additional magnetization measurements of 4 and 5. Further investigations by cyclic voltammetry indicate relatively high oxidation potentials for these NiI compounds between 0.7 and 1.7 V versus Fc/Fc+. Screening reactions with O2 and CO gave first insights on the reaction behaviour of the NiI phosphine complexes towards small molecules with formation of mixed phosphine- CO-NiI complexes and oxidation processes yielding new NiI and/or NiII derivatives. Moreover, 4 reacted with CH2Cl2 at RT to give a dimeric NiII ylide complex (4c). As CH2Cl2 is a rather stable alkyl halide with relatively high C@Cl bond energies, 4 appears to be a suitable reagent for more general C@Cl bond activation reactions. [ABSTRACT FROM AUTHOR]

To provide a better understanding of the recently published pure metalorganic NiI species, [Ni(cod)2][Al(ORF)4] (1) [cod = 1,5- cyclooctadiene, RF = C(CF3)3], further characterizations were performed and analyzed. Thus, the solvation of 1 in THF was examined by EPR, surprisingly disclosing the initiation of a disproportionation reaction to [NiII(THF)6][Al(ORF)4]2 (3) and Ni0. Further studies con- cerning the ability of 1 to activate small molecules exhibit the formation of a remarkable [Ni3S2(cod)3]2+ cluster (5) in an oxidation reaction with S8, while EPR measurements of the resulting product in a reaction with oxygen indicate a possible coordination of O2. Single crystal X-ray structures as well as spectroscopic analyses of 3 and 5 are described. [ABSTRACT FROM AUTHOR]