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Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Palladium-Catalyzed Directed Aldehyde C-H Arylation of Quinoline-8-carbaldehydes: Exploring the Reactivity
Dinesh Gopichand Thakur1,2, Tapan Sahoo1,2, Chiranjit Sen1,2
1Natural Products and Green Chemistry Division, Central Salt and Marine Chemicals Research Institute (CSIR), G. B. Marg, Bhavnagar 364002, Gujarat, India.
Abstract:
We have developed a method for Pd-catalyzed direct C-H arylation of quinoline-8-carbaldehydes with either aryl iodides or aryl diazonium salts for the synthesis of aryl quinolinyl ketones. Aryl iodide substituted with an electron-donating group favors the reaction, whereas aryl diazonium salt substituted with an electron-withdrawing group showed excellent reactivity. A range of aryl quinolinyl ketones were synthesized in good-to-excellent yields, with very good functional group tolerance. Our methodology was successfully applied to synthesize highly potent tubulin polymerization inhibitors and can be easily scaled up to a gram scale.
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