Abstract
Halogenated N-heterocycles are an essential structural building-block in medicinal chemistry. Herein, we describe an economical and efficient protocol for regioselective halogenation of several N-heterocycles (pyrimidines, pyrazole, 2-aminopyridine, theophylline and imidazo[1,2-a]pyridine) using BF3 doped montmorillonite (BF3@K10). The new catalyst was characterized by FTIR, 11B NMR, XRD, SEM and EDS spectroscopy. The developed strategy provides easy and fast access to iodo-, bromo-, and chloro- N-heterocycles under mild conditions. The developed strategy is used to synthesized nine new halogenated derivatives of pyrimidines. This reaction under conventional heating or microwave conditions is simple, general, affording good to excellent yields of products, in the presence of BF3@K10 as an eco-friendly, inexpensive, and efficient catalyst, this reaction is simple and affording good to excellent yields of products under conventional heating or microwave conditions. This protocol is clearly superior to conventional route offering short reaction times, high yields, and easy workup..</jats:p>