Work

Synthesis and Reactivity of (N2P2)Ni Complexes Stabilized by a Novel Diphosphonite Pyridinophane Ligand

Year: 2021

Type: preprint

Abstract: A series of (N2P2)NiII complexes (N2P2 = P,P’-ditertbutyl-2,11-diphosphonito[3.3](2,6)pyridinophane) stabilized by a modified tetradentate pyridinophane ligand containing two phosphonite groups were synthesized and characterized. Cyclic voltammetry (CV) studies revealed the accessibility of the NiI oxidation state at moderate redox potentials for these NiII complexes. In situ EPR, low-temperature UV-vis, and electrochemical studies were employed to detect the formation of NiI species during the reduction of NiII precursors. Furthermore, the [(N2P2)NiI(CNtBu)](SbF6) complex was isolated upon reduction of the NiII precursor with 1 equiv of CoCp2, and was characterized by EPR and X-ray photoelectron spectroscopy (XPS). Finally, the (N2P2)NiIIBr2 complex acts as an efficient catalyst for the Kumada cross-coupling of an aryl halide with an aryl or alkyl Grignard, suggesting that the N2P2 ligand can support the various Ni species involved in the catalytic C-C bond formation reactivity.

Source: ChemRxiv

DOI: 10.26434/chemrxiv.13514434

Authors: Kei Fuchigami, Michael B. Watson, Giang N. Tran, Nigam P. Rath, Liviu M. Mirica

Institutions: Washington University in St. Louis, University of Illinois Urbana-Champaign, University of Missouri–St. Louis

Language: English

Topic: Organometallic Complex Synthesis and Catalysis

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funder: U.S. Department of Energy

Award: NEW; NOVEL PALLADIUM CATALYSTS FOR THE OXIDATIVE OLIGOMERIZATION OF METHANE & CARBON DIOXIDE REDUCTION; PI - LIVIU MIRICA