Totally Synthetic by Paul H. Docherty, 15 October 2006
Total Synthesis of ent-Clavilactone B
I. Larrosa, M. I. Da Silva, P. M. Gómez, P. Hannen, E. Ko, S. R. Lenger, S. R. Linke, A. J. P. White, D. Wilton, A. G. M. Barrett, J. Am. Chem. Soc. 2006, 128, 14042-14043
A nice, and short total synthesis of this antibiotic/antifungal agent, using an interesting three-component-coupling strategy. First, the retroanalysis:
The larger substrate for this tranformation was assembled quickly, and the coupling completed by addition of methyl allyl grignard to the benzyne. The grignard reagent generated in situ was then reacted with the aldehyde partner, completing the coupling.
The required diastereoisomer was recieved along with 21% of the undesired, but this was recycled using the aluminium species shown below.
Nice work, and completed in ten steps.