A highly efficient precatalytic system (XPhos-PdG2) for the Suzuki–Miyaura cross-coupling of 7-chloro-1H-pyrrolo[2,3-c]pyridine employing low catalyst loading

  • Bhaskaran Savitha
  • Eeda Koti Reddy
  • D. Parthasarathi
  • Rajeesh Pakkath
  • Ranjith Pakkath Karuvalam
  • C. S. Ananda Kumar
  • K. R. Haridas
  • M. Syed Ali PadushaEmail author
  • Ayyiliath M. SajithEmail author
Original Article


An expedient catalytic method for the synthesis of diverse 7-(hetero) aryl-1H-pyrrolo[2,3-c]pyridine analogues via microwave-assisted Suzuki–Miyaura cross-coupling reaction with excellent yield was developed. The method is found to be compatible with various boronic acids and potassium organotrifluoroborates. The formation of highly stable monoligated catalytic species is found to be instrumental in driving the reactions to excellent conversions in Suzuki–Miyaura coupling. Herein, we report our findings on the use of a highly efficient precatalytic system (XPhos-PdG2), containing a bulky monodentate biaryl ligand which allows the rapid reductive elimination to form the true monoligated Pd(0) catalytic species, thereby facilitating the Suzuki coupling reaction of 7-chloro, 6-azaindole system containing unprotected free N–H group with excellent conversions employing low catalyst loadings. Also, we observed that the use of near stoichiometric potassium organotrifluoroborate reagents as alternative coupling partners for boronic acids, which are prone to protodeboronation, resulted in excellent conversions.

Graphical abstract


7-chloro-1H-pyrrolo[2,3-c]pyridine XPhos-PdG2 Suzuki–Miyaura cross-coupling 

Supplementary material

11030_2018_9904_MOESM1_ESM.pdf (9.7 mb)
Supplementary material 1 (PDF 9963 kb)


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Postgraduate and Research Department of Chemistry, Jamal Mohamed CollegeBharathidasan UniversityTiruchirappalliIndia
  2. 2.Department of ChemistryVignan’s Foundation for Science, Technology and Research –VFSTR (Deemed to be University)Vadlamudi, GunturIndia
  3. 3.School of Chemical SciencesKannur UniversityKannurIndia
  4. 4.Postgraduate and Research Department of Chemistry, Kasaragod Government CollegeKannur UniversityKasaragodIndia
  5. 5.Visvesvaraya Technological University, CPGSMuddenahalliIndia
  6. 6.Centre for Material ScienceUniversity of MysoreMysoreIndia

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