text: The closest competing method to IMHR is radical cyclization. Radical cyclizations are often reductive, which can cause undesired side reactions to occur if sensitive substrates are employed. The IMHR, on the other hand, can be run under reductive conditions if desired. Unlike the IMHR, radical cyclization does not require the coupling of two sp-hybridized carbons. In some cases, the results of radical cyclization and IMHR are complementary.