Pd-Catalyzed C-H Halogenation of Indolines and Tetrahydroquinolines with Removable Directing Group
Ashfaq Ahmad1, Himangsu Sekhar Dutta2, Mohit Kumar2
1Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031, India.
Abstract:
Pd-catalyzed directing-group-assisted regioselective halogenations to C7 of indolines and C8 of tetrahydroquinolines were achieved in good to excellent yields. The practicality and utility of the developed method have been illustrated by various functional group transformations such as arylation, alkenylation, cyanation, and silylation utilizing the installed synthetic handle. The concise synthesis of primaquine, an antimalarial drug, and formal syntheses of two bioactive natural products, hippadine and pratosine, have also been demonstrated.
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