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Productive Alkyne Metathesis with "Canopy Catalysts" Mandates Pseudorotation.

ABSTRACT: Molybdenum alkylidyne complexes of the "canopy catalyst" series define new standards in the field of alkyne metathesis. The tripodal ligand framework lowers the symmetry of the metallacyclobutadiene complex formed by [2 + 2] cycloaddition with the substrate and imposes constraints onto the productive [2 + 2] cycloreversion; pseudorotation corrects this handicap and makes catalytic turnover possible. A combined spectroscopic, crystallographic, and computational study provides insights into this unorthodox mechanism and uncovers the role that metallatetrahedrane complexes play in certain cases.

SUBMITTER: Haack A

PROVIDER: S-EPMC8154524 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Productive Alkyne Metathesis with "Canopy Catalysts" Mandates Pseudorotation.

Haack Alexander A Hillenbrand Julius J Leutzsch Markus M van Gastel Maurice M Neese Frank F Fürstner Alois A

Journal of the American Chemical Society 20210407 15

Molybdenum alkylidyne complexes of the "canopy catalyst" series define new standards in the field of alkyne metathesis. The tripodal ligand framework lowers the symmetry of the metallacyclobutadiene complex formed by [2 + 2] cycloaddition with the substrate and imposes constraints onto the productive [2 + 2] cycloreversion; pseudorotation corrects this handicap and makes catalytic turnover possible. A combined spectroscopic, crystallographic, and computational study provides insights into this u ...[more]

PMID: 33826335

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