This document describes novel methods for regioselectively iodinating heterocycles using milder reaction conditions. The author developed methods to iodinate N-methylpyrrole and dibenzofuran with good to high yields. For N-methylpyrrole, trifluoroacetic acid was used as an activator with N-iodosuccinimide as the iodine source in tetrahydrofuran, achieving both high yield and regioselectivity. Dibenzofuran was also iodinated in good yield using these conditions as well as with N-iodosuccinimide in hexafluoro-2-propanol. The results indicate these mild conditions can achieve