Iodine‐Mediated sp3 C−H Amination Reactions Forming α‐Amino Ketones/Esters and Fused Imidazoles

Abstract

AbstractAn iodine‐mediated direct sp3 C−H amination reaction has been established for the synthesis of nitrogen‐containing compounds from readily available substrates under transition‐metal‐free conditions. The I2‐promoted amination of ketones/esters with cyclic or acyclic secondary amines using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as a base led to the formation of various α‐amino ketone or ester products including two medications, Amfepramone and Plavix. Sequential I2‐mediated sp3 C−H amination and condensation of ketones with 2‐aminopyridines in the presence of Na2CO3 produced a series of imidazo[1,2‐a]pyridines and related fused imidazoles in a one‐pot reaction. This synthetic method is operationally simple and can be conveniently conducted on a gram scale under mild reaction conditions.