Total Synthesis of Brevenal Jon D. Rainier Department of Chemistry, University of Utah. J. Am. Chem. Soc. 2011, 133, 3208–3216

Dinoflagellate-derived marine ladder toxin Interesting pentacyclic structure Fused ether architectures

Olefinic Ester and Diene Ring-Closing Metathesis Using a Reduced Titanium Alkylidene: J. AM. CHEM. SOC. 2007, 129,

Synthesis of Brevenal’s E-Ring Precursor: “Rubottom oxidation”

A Novel Carbon-Carbon Bond-Forming Reaction of Triflates with Copper(1)-Catalyzed Grignard Reagents: One-pot double alkylation strategy. J. Org. Chem. 1990, 55,4417–422.

34 was isolated as an inseparable mixture of diastereomers as a result of the poor selectivity in the epoxidation reaction made this approach untenable and forced us to modify our strategy.

model bicyclic enol ether 39 comes from the oxidation of ZnMe 2 by the epoxide from 31 and the subsequent transfer of methoxide to the epoxide

Tetrahedron Letters 51 (2010) 3960–3961

our spectroscopic data for 49 did not match that previously reported. While not definitively established, we presume that pentacycle 49 differs from the brevenal core at C(23). lithium di-t-butyl biphenylide (LiDBB)

Brevenal Retrosynthesis-2:

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