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

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 delta-lactam was obtained. An oxindole product was subjected to substitution reactions to afford 3,3-diaryloxindoles with two different aryl groups.

Automated summary

3-Aryloxindole derivatives were synthesized via a Friedel-Crafts-type cyclization, catalyzed by a trimethylsilyl tricyanopalladate complex. Various diethyl phosphates derived from N-arylmandelamides were efficiently converted into oxindoles, with the use of N,N-dibenzylamide leading to a benzo-fused delta-lactam. Substitution reactions on oxindole products yielded 3,3-diaryloxindoles with two different aryl groups.