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Reductions of challenging organic substrates by a nickel complex of a noninnocent crown carbene ligand.

ABSTRACT: The first crown-tetracarbene complex of Ni(II) has been prepared, and its crystal structure determined. The complex can be reduced by Na/Hg, with an uptake of two electrons. The reduced complex reductively cleaves arenesulfonamides, including those derived from secondary aliphatic amines, and effects Birch reduction of anthracenes as well as reductive cleavage of stilbene oxides. Computational studies show that the orbital that receives electrons upon reduction of the complex 2 is predominantly based on the crown carbene ligand and also that the HOMO of the parent complex 2 is based on the ligand.

SUBMITTER: Findlay NJ

PROVIDER: S-EPMC3662396 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Reductions of challenging organic substrates by a nickel complex of a noninnocent crown carbene ligand.

Findlay Neil J NJ Park Stuart R SR Schoenebeck Franziska F Cahard Elise E Zhou Sheng-Ze SZ Berlouis Leonard E A LE Spicer Mark D MD Tuttle Tell T Murphy John A JA

Journal of the American Chemical Society 20101101 44

The first crown-tetracarbene complex of Ni(II) has been prepared, and its crystal structure determined. The complex can be reduced by Na/Hg, with an uptake of two electrons. The reduced complex reductively cleaves arenesulfonamides, including those derived from secondary aliphatic amines, and effects Birch reduction of anthracenes as well as reductive cleavage of stilbene oxides. Computational studies show that the orbital that receives electrons upon reduction of the complex 2 is predominantly ...[more]

PMID: 20961105

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