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Low catalyst loadings in olefin metathesis: synthesis of nitrogen heterocycles by ring-closing metathesis.

ABSTRACT: A series of ruthenium catalysts have been screened under ring-closing metathesis (RCM) conditions to produce five-, six-, and seven-membered carbamate-protected cyclic amines. Many of these catalysts demonstrated excellent RCM activity and yields with as low as 500 ppm catalyst loadings. RCM of the five-membered carbamate series could be run neat, the six-membered carbamate series could be run at 1.0 M, and the seven-membered carbamate series worked best at 0.2-0.05 M.

SUBMITTER: Kuhn KM

PROVIDER: S-EPMC3871858 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Low catalyst loadings in olefin metathesis: synthesis of nitrogen heterocycles by ring-closing metathesis.

Kuhn Kevin M KM Champagne Timothy M TM Hong Soon Hyeok SH Wei Wen-Hao WH Nickel Andrew A Lee Choon Woo CW Virgil Scott C SC Grubbs Robert H RH Pederson Richard L RL

Organic letters 20100301 5

A series of ruthenium catalysts have been screened under ring-closing metathesis (RCM) conditions to produce five-, six-, and seven-membered carbamate-protected cyclic amines. Many of these catalysts demonstrated excellent RCM activity and yields with as low as 500 ppm catalyst loadings. RCM of the five-membered carbamate series could be run neat, the six-membered carbamate series could be run at 1.0 M, and the seven-membered carbamate series worked best at 0.2-0.05 M. ...[more]

PMID: 20141172

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