Abstract In this work, we conducted a study of 7‐ exo ‐ trig cyclizations mechanism involving aryl, vinyl, and alkyl radicals on oxime ethers. Initially, the reaction of brominated oxime ether 9 a with (TMS) 3 SiH and AIBN gave rise to aryl radicals that underwent a 7‐ exo ‐ trig cyclization on the oxime ether, yielding dibenzoxepine 10 a , and the ipso reaction and reduction products were obtained as well. Approximate rate constants at 80 °C for the 7‐ exo ‐ trig (1.0×10 8 s −1 ) and the ipso cyclization (4.3×10 7 s −1 ) were determined by competition experiments. DFT calculations showed good agreement with the experimental results. The reduction rate constant of the N ‐alkoxyaminyl radical with (TMS) 3 SiH was calculated to be 4.1×10 −1 M −1 s −1 ; while the rate constants for the 7‐ exo ‐ trig cyclizations of vinyl and alkyl radicals on the oxime ether were estimated in the ranges of 10 6 s −1 –10 8 s −1 and 10 3 s −1 –10 8 s −1 , respectively. The 7‐ exo ‐ trig cyclization reactions involving aryl, vinyl, and alkyl radicals with oxime ethers were found to be an exothermic and irreversible process, with the oximic carbon showing a preference for nucleophilic alkyl radicals. This kinetic study contributes to the deeper understanding of radical‐mediated cyclizations, enabling the efficient design of complex synthetic routes.