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Synthesis of Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds through stereoselective catalytic cross-metathesis.

ABSTRACT: The first examples of catalytic cross-metathesis (CM) reactions that furnish Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds are disclosed. Products are generated with high Z selectivity by the use of a W-based monoaryloxide pyrrolide (MAP) complex (up to 91% yield and >98:2 Z:E). The more sterically demanding Z-alkenylboron species are obtained in the presence of Mo-based MAP complexes in up to 93% yield and 97% Z selectivity. Z-selective CM with 1,3-dienes and aryl olefins are reported for the first time. The utility of the approach, in combination with catalytic cross coupling, is demonstrated by a concise and stereoselective synthesis of anticancer agent combretastatin A-4.

SUBMITTER: Kiesewetter ET

PROVIDER: S-EPMC3649762 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Synthesis of Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds through stereoselective catalytic cross-metathesis.

Kiesewetter Elizabeth T ET O'Brien Robert V RV Yu Elsie C EC Meek Simon J SJ Schrock Richard R RR Hoveyda Amir H AH

Journal of the American Chemical Society 20130415 16

The first examples of catalytic cross-metathesis (CM) reactions that furnish Z-(pinacolato)allylboron and Z-(pinacolato)alkenylboron compounds are disclosed. Products are generated with high Z selectivity by the use of a W-based monoaryloxide pyrrolide (MAP) complex (up to 91% yield and >98:2 Z:E). The more sterically demanding Z-alkenylboron species are obtained in the presence of Mo-based MAP complexes in up to 93% yield and 97% Z selectivity. Z-selective CM with 1,3-dienes and aryl olefins ar ...[more]

PMID: 23586708

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