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Abstract Addition of sub‐stoichiometric quantities of PEt3and diphenyl disulfide to a solution of [Ni(1,5‐cod)2] generates a mixture of [Ni3(SPh)4(PEt3)3] (1), unreacted [Ni(1,5‐cod)2], and [(1,5‐cod)Ni(PEt3)2], according to1H and31P{1H} NMR spectroscopic monitoring of the in situ reaction mixture. On standing, complex1converts into [Ni4(S)(Ph)(SPh)3(PEt3)3] (2), via formal addition of a “Ni(0)” equivalent, coupled with a CS oxidative addition step, which simultaneously generates the Ni‐bound phenyl ligand and the μ3‐sulfide ligand. Upon gentle heating, complex2converts into a mixture of [Ni5(S)2(SPh)2(PEt3)5] (3) and [Ni8(S)5(PEt3)7] (4), via further addition of “Ni(0)” equivalents, in combination with a series of C–S oxidative addition and CC reductive elimination steps, which serve to convert thiophenolate ligands into sulfide ligands and biphenyl. The presence of1–4in the reaction mixture is confirmed by their independent syntheses and subsequent spectroscopic characterization. Overall, this work provides an unprecedented level of detail of the early stages of Ni nanocluster growth and highlights the fundamental reaction steps (i.e., metal atom addition, CS oxidative addition, and CC reductive elimination) that are required to grow an individual cluster.
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This content will become publicly available on April 17, 2026
Sulfonyl fluoride activation via S-F and C-S bond cleavage by a Ni(0) bis-bidentate N- heterocyclic carbene complex
This work investigates possible mechanisms and intermediates in the reactivity of p-toluenesulfonyl fluoride with a new bidentate N-heterocyclic carbene (NHC) nickel complex, (MesNHC2oXy)Ni(COD) (Mes = 2,4,6-trimethylphenyl, oXy = ortho-xylyl, COD = cyclooctadiene). (MesNHC2oXy)Ni(COD) was synthesized from the corresponding bis(imidazolium) salt precursor, [MesNHC2oXy][Br]2, and both were structurally characterized. (MesNHC2oXy)Ni(COD) reacts with one equivalent of p-toluenesulfonyl fluoride to furnish (MesNHC2oXy)Ni(2-SO2), HF, and ½ equivalent of 4,4’-dimethylbiphenyl. (MesNHC2oXy)Ni(2-SO2) was structurally characterized and has a unique side-on SO2 coordination mode with a Ni-S-O angle of 60.49(5)°. DFT calculations of (MesNHC2oXy)Ni(2-SO2) are consistent with a Ni(II) center and an activated SO2 fragment. DFT calculations also support an initial oxidative addition at either the S-F or S-C positions, which have similar energetics.
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- Award ID(s):
- 2350537
- PAR ID:
- 10623928
- Publisher / Repository:
- ChemRxiv
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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