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Updated: Jun 8, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Heteroatom-directed reverse Wacker oxidations. Synthesis of the reported structure of (-)-herbaric acid
Peter J Choi1, Jonathan Sperry, Margaret A Brimble
1Department of Chemistry, University of Auckland, 23 Symonds St., Auckland, New Zealand.
Abstract:
A microwave-assisted chemoenzymatic resolution has been used to install the C3 stereocenter of the reported structure of the fungal metabolite herbaric acid in high enantiomeric excess. The synthesis and stereochemical assignment was accomplished using a completely regioselective anti-Markovnikov addition of water to vinylphthalide 3, achieved using a heteroatom-directed Wacker oxidation that proceeds with retention of stereochemistry. These results establish that so-called "reverse" Wacker oxidations are a viable alternative to hydroboration/oxidation procedures.
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