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Characterization of Tunable Radical Metal-Carbenes: Key Intermediates in Catalytic Cyclopropanation.

ABSTRACT: A new class of radical metal-carbene complex has been characterized as having Fischer-like orbital interactions and adjacent ? acceptor stabilization. Density Functional Theory (DFT) along with Natural Bond Orbital (NBO) analysis and Charge Decomposition Analysis (CDA) has given insight into the electronics of this catalytic intermediate in an open-shell cobalt-porphyrin, [Co(Por)], system. The complex has a single bond from the metal to the carbene and has radical character with localized spin density on the carbene carbon. In addition, the carbene carbon is found to be nucleophilic and "tunable" through the introduction of different ?-carbon substituents. Finally, based on these findings, rational design strategies are proposed which should lead to the enhancement of catalytic activity.

SUBMITTER: Belof JL

PROVIDER: S-EPMC3105361 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Characterization of Tunable Radical Metal-Carbenes: Key Intermediates in Catalytic Cyclopropanation.

Belof Jonathan L JL Cioce Christian R CR Xu Xue X Zhang X Peter XP Space Brian B Woodcock H Lee HL

Organometallics 20110401 10

A new class of radical metal-carbene complex has been characterized as having Fischer-like orbital interactions and adjacent π acceptor stabilization. Density Functional Theory (DFT) along with Natural Bond Orbital (NBO) analysis and Charge Decomposition Analysis (CDA) has given insight into the electronics of this catalytic intermediate in an open-shell cobalt-porphyrin, [Co(Por)], system. The complex has a single bond from the metal to the carbene and has radical character with localized spin ...[more]

PMID: 21643517

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