The development of a Lewis acid-catalyzed, intramolecular ring-opening benzannulation of 5-(indolyl)2,3-dihydrofuran acetals is described. The resulting 1-hydroxycarbazole-2-carboxylates are formed in up to 90% yield in 1 h. The dihydrofuran acetals are readily accessed from the reactions of enol ethers and α-diazo-β-indolyl-β-ketoesters. To highlight the method’s synthetic utility, a formal total synthesis of murrayafoline A, a bioactive carbazole-containing natural product, was undertaken.

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Herein, a general approach to intermolecular benzylic C(sp3)−H alkylation of methyl‐substituted arenes is reported using metal carbenes derived from N‐aryl‐α‐diazo‐β‐amidoesters and dirhodium catalysts. Alkylated products were formed in up to 81 % yield with demonstrated functional group tolerance, outpacing previous literature. The unique amide‐ester scaffolding can be exploited through various derivatizations for broad synthetic utility and provides a starting point for the development of selectivity rules and reactivity profiles for these intermolecular C(sp3)−H functionalizations.