The Total Synthesis of Mollanol A by a Convergent Strategy

Abstract

Here, we briefly highlight our 15-step total synthesis of mollanol A, the first isolated member of the mollane-type grayanoids, which relied on a convergent strategy. A Stille coupling and a vinylogous aldol reaction/intramolecular oxa-Michael addition sequence were used to assemble the two fragments that featured most of the important chiral centers and nearly all the essential oxidation states of the natural product. The bicyclo[3.2.1]octane fragment was synthesized by using an InCl₃-catalyzed Conia–ene cyclization reaction. The challenging tetrasubstituted alkene was constructed through a 1,4-reduction of the conjugated alkenes at a late stage.

1 Introduction

2 Total Synthesis of Mollanol A

3 Conclusion

Key words

grayanoids - total synthesis - mollanol A - convergent synthesis - Conia–ene cyclization - intramolecular oxa-Michael addition

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