• Venkata Reddy Regalla Department of Chemistry, Koneru Lakshmaiah University, Vaddeswaram, Guntur, Andhra Pradesh, India.
  • Rama Krishnam Raju Addada Department of Chemistry, Koneru Lakshmaiah University, Vaddeswaram, Guntur, Andhra Pradesh, India.
  • Venkat Swamy Puli Department of Chemistry, Koneru Lakshmaiah University, Vaddeswaram, Guntur, Andhra Pradesh, India.
  • Abhishek S Saxena GVK Biosciences Private Limited, Medicinal Chemistry Division, 28A, IDA, Nacharam, Hyderabad, Telangana, India.
  • Anindita Chatterjee Department of Chemistry, Koneru Lakshmaiah University, Vaddeswaram, Guntur, Andhra Pradesh, India.


Objective: The aim of the present study is to synthesize 2,4-disubstituted oxazoles through palladium/copper comediated direct arylation reaction.

Methods: 2,4-disubstituted oxazoles (3a-i) have been synthesized by the reaction of 4-substituted oxazole with aryl bromide in the presence of KOH , CuI and Pd(PPh3)4 in dimethoxyethane. Titled compounds (3a-i) were obtained in good yields using an expedient two-step synthesis of 2,4-disubstituted oxazoles from commercially available starting materials

Results: The structures of the newly synthesized compounds were characterized by Fourier-transform infrared, 1H NMR, 13C NMR, and mass spectral studies. This method can be an efficient method for the synthesis of 2,4-disubstituted oxazoles (3a-i).

Conclusion: Pd(PPh3)4 and CuI cocatalytic system direct arylation of 4-aryl/alkyl oxazoles with various aryl bromides has been developed to generate 2,4-disubstituted oxazoles. The high functional group tolerance and the speed of the reaction afford this method appropriate for the combinatorial synthesis of a variety of 2,4-disubstituted oxazoles.

Keywords: Oxazoles, Arylation, Palladium/copper.


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How to Cite
Regalla, V. R., R. K. R. Addada, V. S. Puli, A. S. Saxena, and A. Chatterjee. “HIGHLY EFFICIENT SYNTHESIS OF 2,4-DISUBSTITUTED OXAZOLES THROUGH PALLADIUM/COPPER COMEDIATED DIRECT ARYLATION REACTION”. Asian Journal of Pharmaceutical and Clinical Research, Vol. 11, no. 8, Aug. 2018, pp. 511-4, doi:10.22159/ajpcr.2018.v11i8.26125.
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