Silyl Cyanopalladate-Catalyzed Friedel–Crafts-Type Cyclization Affording 3-Aryloxindole Derivatives

Abstract

3-Aryloxindole derivatives were synthesized through a Friedel–Crafts-type cyclization. The reaction was catalyzed by a trimethylsilyl tricyanopalladate complex generated in situ from trimethylsilyl cyanide and Pd(OAc)₂. Wide varieties of diethyl phosphates derived from N-arylmandelamides were converted almost quantitatively into oxindoles. When N,N-dibenzylamide was used instead of an anilide substrate, a benzo-fused δ-lactam was obtained. An oxindole product was subjected to substitution reactions to afford 3,3-diaryloxindoles with two different aryl groups.

Key words

Lewis acid catalysis - Friedel–Crafts reaction - cyclization - oxindoles - S_N1 reaction

Publikationsverlauf

Eingereicht: 24. Dezember 2020

Angenommen nach Revision: 26. Januar 2021

Accepted Manuscript online:
26. Januar 2021

Artikel online veröffentlicht:
10. Februar 2021

• References and Notes

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Under the photoirradiation conditions, the S_RN1-reaction of o-chloroanilides affords the 3-aryloxindole derivatives, see:
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