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Co-complexes derived from alkene insertion to alkyne-dicobaltpentacarbonyl complexes: insight into the regioselectivity of pauson-khand reactions of cyclopropenes.

ABSTRACT: Described are the X-ray crystallographic and spectral properties of Co-complexes that were isolated from two Pauson-Khand reactions of chiral cyclopropenes. These are the first examples of isolated Co-complexes derived from the putative alkene-insertion intermediates of Pauson-Khand reactions. The binuclear Co-complexes are coordinated to mu-bonded, five-carbon "flyover" carbene ligands. It is proposed that the complexes result from cyclopropane fragmentation subsequent to alkene insertion. The observation of these metal complexes provides a rationale for the origin of regioselectivity in Pauson-Khand reactions of cyclopropenes.

SUBMITTER: Pallerla MK

PROVIDER: S-EPMC2667904 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Co-complexes derived from alkene insertion to alkyne-dicobaltpentacarbonyl complexes: insight into the regioselectivity of pauson-khand reactions of cyclopropenes.

Pallerla Mahesh K MK Yap Glenn P A GP Fox Joseph M JM

The Journal of organic chemistry 20080719 16

Described are the X-ray crystallographic and spectral properties of Co-complexes that were isolated from two Pauson-Khand reactions of chiral cyclopropenes. These are the first examples of isolated Co-complexes derived from the putative alkene-insertion intermediates of Pauson-Khand reactions. The binuclear Co-complexes are coordinated to mu-bonded, five-carbon "flyover" carbene ligands. It is proposed that the complexes result from cyclopropane fragmentation subsequent to alkene insertion. The ...[more]

PMID: 18637694

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