Further developments in the synthesis of lamellarin alkaloids via direct metal–halogen exchange

Direct metal–halogen exchange of 2-bromopyrrole carbonate derivatives with tert-butyllithium followed by the intramolecular lactonization of the resulting 2-pyrrole anion onto the carbonate provided the corresponding lamellarins in moderate to good yield. The lamellarin framework could be obtained from the direct metal–halogen exchange strategy in a 26–33% overall yield over 5–6 steps.