Application of a Palladium‐Catalyzed C−H Functionalization/Indolization Method to Syntheses of cis‐Trikentrin A and Herbindole B

Abstract

We describe herein formal syntheses of the indole alkaloids cis-trikentrin A and herbindole B from a common meso-hydroquinone intermediate prepared by a ruthenium-catalyzed [2+2+1+1] cycloaddition that has not been used previously in natural product synthesis. Key steps include a sterically demanding Buchwald-Hartwig amination as well as a unique C(sp(3) )-H amination/indole formation. Studies toward a selective desymmetrization of the meso-hydroquinone are also reported.

Recent Advances in Methylation: A Guide for Selecting Methylation Reagents

“…In cross-coupling catalysis, Stille coupling is still aw idely used method. [191] In this section, Ih ighlight the recent applications of Me 4 Sn in CÀCf ormation by using aryl triflates [192] and aryl halides (Ar-I, [193] Ar-Br, [194] and Ar-Cl) [195] as the electrophile substrates. Figure 7s howcases selected C-methylated products and different key conditions.…”

Mukaiyama Award: R. Sarpong and S. Chiba / Bayerischer Maximiliansorden: P. Schwille

“…These strategies are implemented using a variety of methods including C−H and C−C functionalizations. In a Communication in Angewandte Chemie , he described a palladium‐catalyzed C−H functionalization/indolization for the synthesis of cis ‐trikentrin A and herbindole B . Sarpong has also been featured with his author profile in Angewandte Chemie…”

Mukaiyama‐Preis: R. Sarpong und S. Chiba / Bayerischer Maximiliansorden: P. Schwille

“…Diese Strategien stützen sich unter anderem auf C‐H‐ und C‐C‐Funktionalisierungen. In einer Angewandte‐Chemie ‐Zuschrift beschrieb er eine palladiumkatalysierte C‐H‐Funktionalisierung nebst Indolisierung zur Synthese von cis ‐Trikentrin A und Herbindole B . Sarpong wurde überdies mit seinem Autoren‐Profil in der Angewandten Chemie vorgestellt…”