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Cobalt-Magnesium and Iron-Magnesium Complexes with Weakened Dinitrogen Bridges.

ABSTRACT: The cooperative binding of N2 by late transition metals and main-group metals is a promising strategy for N-N bond weakening and activation. We report the use of activated Rieke magnesium for reduction of iron and cobalt complexes supported by bulky ?-diketiminate ligands. Binding of N2 is accompanied by assembly of a linear M-NN-Mg-NN-M (M = Co, Fe) core with N-N bonds that are weakened, as judged by infrared spectroscopy. Both the cobalt and iron complexes require THF solvent, because of Mg-THF binding. The cobalt complex can be isolated as a pure solid, but the iron complex is stable only in solution. These results demonstrate the correlation between the binding mode and N-N weakening in heterobimetallic N2 complexes.

SUBMITTER: Dugan TR

PROVIDER: S-EPMC3869404 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Cobalt-Magnesium and Iron-Magnesium Complexes with Weakened Dinitrogen Bridges.

Dugan Thomas R TR Macleod K Cory KC Brennessel William W WW Holland Patrick L PL

European journal of inorganic chemistry 20130801 22-23

The cooperative binding of N<sub>2</sub> by late transition metals and main-group metals is a promising strategy for N-N bond weakening and activation. We report the use of activated Rieke magnesium for reduction of iron and cobalt complexes supported by bulky β-diketiminate ligands. Binding of N<sub>2</sub> is accompanied by assembly of a linear M-NN-Mg-NN-M (M = Co, Fe) core with N-N bonds that are weakened, as judged by infrared spectroscopy. Both the cobalt and iron complexes require THF sol ...[more]

PMID: 24367236

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