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A Highly Efficient Synthesis of Z-Macrocycles Using Stereoretentive, Ruthenium-Based Metathesis Catalysts.

ABSTRACT: A highly efficient, Z-selective ring-closing metathesis system for the formation of macrocycles using a stereoretentive, ruthenium-based catalyst supported by a dithiolate ligand is reported. The catalyst is remarkably active as observed in initiation experiments showing complete catalyst initiation at -20?°C within 10?minutes. Macrocyclization reactions generated Z-products from easily accessible diene starting materials bearing a Z-olefin moiety. This approach provides a more efficient and selective route to Z-macrocycles relative to previously reported systems. Reactions were completed within shorter reaction times, and turnover numbers of up to 100 could be achieved. Macrocyclic lactones ranging in size from twelve- to seventeen-membered rings were synthesized in moderate to high yields (67-79?%) with excellent Z-selectivity (95-99?%).

SUBMITTER: Ahmed TS

PROVIDER: S-EPMC5683173 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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A Highly Efficient Synthesis of Z-Macrocycles Using Stereoretentive, Ruthenium-Based Metathesis Catalysts.

Ahmed Tonia S TS Grubbs Robert H RH

Angewandte Chemie (International ed. in English) 20170712 37

A highly efficient, Z-selective ring-closing metathesis system for the formation of macrocycles using a stereoretentive, ruthenium-based catalyst supported by a dithiolate ligand is reported. The catalyst is remarkably active as observed in initiation experiments showing complete catalyst initiation at -20 °C within 10 minutes. Macrocyclization reactions generated Z-products from easily accessible diene starting materials bearing a Z-olefin moiety. This approach provides a more efficient and sel ...[more]

PMID: 28644909

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