Transition-metal-free oxidative C5 C–H-halogenation of 8-aminoquinoline amides using sodium halides
作者:Ying Wang、Yang Wang、Kai Jiang、Qian Zhang、Dong Li
DOI:10.1039/c6ob02079h
日期:——
A simple and efficient transition-metal-free oxidative halogenation (Cl, Br) of the C5 C–H bond of 8-aminoquinoline amides has been developed. This method employed low-cost and innoxious sodium halides as halogenation reagents and oxone as an oxidant. The reactions demonstrated air and moisture tolerance, and good functional group compatibility, giving highly selective C5-halogenated products in good
The oxygenation of 8-aminoquinoline amides by benzoyl peroxide at the C5 position in water is developed in the absence of a transition metal catalyst, affording the desired products in moderate to good yields of up to 88%. Mechanism studies reveal that the reaction would involve a radical process.
An oxidant-free electrochemical regioselective chlorination of 8-aminoquinoline amides at ambient temperature in batch and continuous-flow was achieved. Inert DCM was used as the chlorinating reagent. Owing to the continuous-flow setup, the reaction scale up can be achieved conveniently with higher productivity. Moreover, this method has good position-control, and water and air tolerance. Costly quaternary