Pd-catalyzed C–H bond activation of Indoles for Suzuki reaction

  • Isita Banerjee
  • Keshab Ch Ghosh
  • Surajit SinhaEmail author
Regular Article


We present a practical method for Suzuki coupling by which unprotected or N-protected indoles may be selectively arylated in the C2-position through direct C–H bond activation by electrophilic \(\hbox {Pd(TFA)}_{2}\) catalyst. The protocol is operationally simple as it is carried out in dioxane/water mixture, and air as the sole oxidant at room temperature. Various 2-arylated indoles were obtained in good yields. The protocol works for benzofuran, pyrrole and thiophene also.

Graphic abstract

Selective C-2 arylation of heterocycles using Pd(II) catalyst via C–H activation was performed under ambient condition. C3–C2 migration of organopalladium intermediate controls the reaction pathway.


C–H arylation of indole boronic acid Pd catalysis air 



Financial support from the Science and Engineering Research Board, Department of Science and Technology, Government of India (Grant No. (SR/S1/OC/0087/2012) is gratefully acknowledged. I. B. and K.C.G are thankful to Council for Scientific and Industrial Research (CSIR) New Delhi for the fellowship.

Supplementary material

12039_2019_1649_MOESM1_ESM.pdf (3.3 mb)
Supplementary material 1 (pdf 3335 KB)


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Copyright information

© Indian Academy of Sciences 2019

Authors and Affiliations

  1. 1.School of Applied and Interdisciplinary SciencesIndian Association for the Cultivation of ScienceKolkataIndia

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