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Highly Z- and enantioselective ring-opening/cross-metathesis reactions catalyzed by stereogenic-at-Mo adamantylimido complexes.

ABSTRACT: The first highly Z- and enantioselective class of ring-opening/cross-metathesis reactions is presented. Transformations are promoted in the presence of <2 mol % of chiral stereogenic-at-Mo monoaryloxide complexes bearing an adamantylimido ligand that are prepared and used in situ. Reactions involve meso oxabicyclic substrates and afford the desired pyrans in 50-85% yield and up to >98:<2 enantiomer ratio. Importantly, the desired chiral pyrans thus obtained bear a Z olefin either exclusively (>98:<2 Z/E) or predominantly (>or=87:13 Z/E).

SUBMITTER: Ibrahem I

PROVIDER: S-EPMC2681245 | biostudies-other | 2009 Mar

REPOSITORIES: biostudies-other

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Highly Z- and enantioselective ring-opening/cross-metathesis reactions catalyzed by stereogenic-at-Mo adamantylimido complexes.

Ibrahem Ismail I Yu Miao M Schrock Richard R RR Hoveyda Amir H AH

Journal of the American Chemical Society 20090301 11

The first highly Z- and enantioselective class of ring-opening/cross-metathesis reactions is presented. Transformations are promoted in the presence of <2 mol % of chiral stereogenic-at-Mo monoaryloxide complexes bearing an adamantylimido ligand that are prepared and used in situ. Reactions involve meso oxabicyclic substrates and afford the desired pyrans in 50-85% yield and up to >98:<2 enantiomer ratio. Importantly, the desired chiral pyrans thus obtained bear a Z olefin either exclusively (>9 ...[more]

PMID: 19249833

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