Efficient N-arylation/dealkylation of electron deficient heteroaryl chlorides and bicyclic tertiary amines under microwave irradiation
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Updated: Jun 24, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Hong-Jun Wang1, Yi Wang, Adam J Csakai
1Medicinal Chemistry Department, Albany Molecular Research, Inc (AMRI), Albany, New York 12212, USA. Hong-Jun.Wang@amriglobal.com
Abstract:
A highly efficient procedure was developed for the microwave-assisted synthesis of N-heteroaryl-4-(2-chloroethyl)piperazines and N-heteroaryl-4-(2-chloroethyl)piperidines. Microwave irradiation of electron deficient heteroaryl chlorides with 1,4-diazabicyclo[2.2.2]octane (DABCO) at 160 degrees C for 15 min led to N-heteroaryl-4-(2-chloroethyl)piperazines in good to excellent yields. In a similar manner, microwave irradiation of electron deficient heteroaryl chlorides with quinuclidine at 180 degrees C for 15 min provided N-heteroaryl-4-(2-chloroethyl)piperidines in good to excellent yields. Extension of the method was demonstrated by the development of a one-pot, two-step microwave-assisted protocol for the synthesis of 4-(2-acetoxyethyl)-substituted N-heteroarylpiperazines and N-heteroarylpiperidines to demonstrate the production of a small library in a parallel fashion.
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