A Combined Tamaru Allylation/Olefin Cross-Metathesis Approach for the Total Syntheses of (+/-)-Paniculidine B, (+/-)-Paniculidine C, and 2-Methylcarbazole

Abstract

A concise approach to the total syntheses of racemic paniculidines B and C is described. The route features a combined Tamaru allylation/olefin cross-metathesis sequence for the regiocontrolled synthesis of prenylindole intermediates. In addition, we report a transformation of the prenylated indole into 2-methylcarbazole catalyzed by sulfonic acid-functionalized silica gel.