A Novel and Sustainable Method for the Synthesis of 2-chloro-3-[trans-4-(4-chlorophenyl) cyclohexyl]-1,4-naphthoquinone, accomplished by systematic process development studies - Trans-Cl synthesis


  • Sanjay Sukumar Saralaya SDM Institute of Technology, Ujire.
  • Shashiprabha SDM College (Autonomous), Ujire.
  • Shridhara Kanakamajalu ArkGen Pharma Private Limited, Bangalore.
  • Kuppuswamy Nagarajan Retired Consultant for Alkem Labs and KOP Research Centre, Bangalore.
  • Koottungalmadhom Ramaswamy Ranganathan Retired Head of R & D, Alkem Labs and KOP Research Centre, Bangalore.


2-Chloro-3-[trans-4-(4-chlorophenyl) cyclohexyl]-1, 4-naphthoquinone, 2,3-Dichloro-1, Synthesis, Characterization, Process Development


Present work reports a novel and commercially viable method for the synthesis of 2-chloro-3-[trans-4-(4-chlorophenyl) cyclohexyl]-1,4-naphthoquinone 1, a renowned intermediate of Atovaquone (an antimalarial drug). Majority of the prior arts disclose the synthesis of this intermediate from the expensive starting material 2-chloro-1,4-naphthoquinone 2, in relatively low yield. In this regard, it was considered worthwhile to synthesize 1 by a novel route using cheaper starting material 2,3-dichloro-1,4-naphtoquinone 5, in high yield and purity. In the present study, emphasis was given for selecting the reagents and solvents, optimizing the reaction conditions, recovery and reuse of solvents and silver salt. This optimized novel process is cost effective and would generate less effluent.  

Author Biographies

Sanjay Sukumar Saralaya, SDM Institute of Technology, Ujire.

Department of Chemistry, Sri Dharmasthala Manjunatheshwara Institute of Technology (Affiliated to Visvesvaraya Technological University, Belagavi), Ujire - 574 240, Karnataka, India.

Shashiprabha, SDM College (Autonomous), Ujire.

PG Department of Chemistry, Sri Dharmasthala Manjunatheshwara College (Autonomous), Ujire-574 240, Karnataka, India.

Shridhara Kanakamajalu, ArkGen Pharma Private Limited, Bangalore.

Technical Coordinator, ArkGen Pharma Private Limited, Peenya Industrial Area, Bangalore-560 058, Karnataka, India. 

Kuppuswamy Nagarajan, Retired Consultant for Alkem Labs and KOP Research Centre, Bangalore.

Retired Consultant for Alkem Labs and KOP Research Centre, Bangalore, Karnataka, India.

Koottungalmadhom Ramaswamy Ranganathan, Retired Head of R & D, Alkem Labs and KOP Research Centre, Bangalore.

Retired Head of R & D, Alkem Labs and KOP Research Centre, Bangalore, Karnataka, India.


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