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Synthesis of Linear (Z)-?,?-Unsaturated Esters by Catalytic Cross-Metathesis. The Influence of Acetonitrile.

ABSTRACT: Kinetically controlled catalytic cross-metathesis reactions that generate (Z)-?,?-unsaturated esters selectively are disclosed. A key finding is that the presence of acetonitrile obviates the need for using excess amounts of a more valuable terminal alkene substrates. On the basis of X-ray structure and spectroscopic investigations a rationale for the positive impact of acetonitrile is provided. Transformations leading to various E,Z-dienoates are highly Z-selective as well. Utility is highlighted by application to stereoselective synthesis of the C1-C12 fragment of biologically active natural product (-)-laulimalide.

SUBMITTER: Yu EC

PROVIDER: S-EPMC5169164 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Synthesis of Linear (Z)-α,β-Unsaturated Esters by Catalytic Cross-Metathesis. The Influence of Acetonitrile.

Yu Elsie C EC Johnson Brett M BM Townsend Erik M EM Schrock Richard R RR Hoveyda Amir H AH

Angewandte Chemie (International ed. in English) 20161001 42

Kinetically controlled catalytic cross-metathesis reactions that generate (Z)-α,β-unsaturated esters selectively are disclosed. A key finding is that the presence of acetonitrile obviates the need for using excess amounts of a more valuable terminal alkene substrates. On the basis of X-ray structure and spectroscopic investigations a rationale for the positive impact of acetonitrile is provided. Transformations leading to various E,Z-dienoates are highly Z-selective as well. Utility is highlight ...[more]

PMID: 27634213

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