Synlett 2021; 32(09): 935-939
DOI: 10.1055/a-1373-7017
letter

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

Hamdiye Ece
a   Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 8, Nishi 5, Sapporo, Hokkaido 060-0808, Japan
,
Yuji Tange
a   Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 8, Nishi 5, Sapporo, Hokkaido 060-0808, Japan
,
Taiga Yurino
b   Division of Applied Chemistry and Frontier Chemistry Center, Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo, Hokkaido 060-8628, Japan
,
b   Division of Applied Chemistry and Frontier Chemistry Center, Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Sapporo, Hokkaido 060-8628, Japan
› Author Affiliations
This work was supported by Grants-in-Aid from the Japan Society for the Promotion of Sciences (JSPS) (Nos. 19H02706 and 19K15548). T.Y. also acknowledges support from the Feasibility Study Program of the Frontier Chemistry Center, Faculty of Engineering, Hokkaido University.


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.

Supporting Information



Publication History

Received: 24 December 2020

Accepted after revision: 26 January 2021

Accepted Manuscript online:
26 January 2021

Article published online:
10 February 2021

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