Late stage Pd-catalyzed C-H bond functionalization: A powerful tool for the one step access to arylated Cyproheptadine and cyclobenzaprine derivatives

Abstract

The reactivity of Cyproheptadine and Cyclobenzaprine in Pd-catalyzed arylation via C-H bond functionalizations was investigated. From Cyproheptadine using aryl bromides as aryl sources and 5 mol% of a palladium catalyst, the C10-arylated Cyproheptadine derivatives were regioselectively obtained. The highest yields were obtained with electron-rich aryl bromides, but the reaction tolerated useful functional groups on the aryl bromide such as dimethylamino, methoxy, hydroxyl, alkyl, aryl, fluoro, chloro and trifluoromethyl. Cyclobenzaprine was also reactive under the same reaction conditions. © 2019 Elsevier Science. All rights reserved.