Abstract <p>Search for reactions with nucleon charge exchange in the fragmentation of carbon nuclei with the energy of 300 MeV/nucleon on a thin beryllium target is performed on the FRAGM fragment separator of the TWAC accelerator complex. The experimental setup arranged at the angle of 3.5° with respect to the incident beam has a high momentum resolution. Differential cross sections for yields of ¹¹Be, ¹²B, and ¹²Be nuclei are measured as a function of the momentum of these nuclei. The experimental data are compared with theoretical predictions of various nucleus–nucleus interaction models and other experimental results. Nucleon charge-exchange processes in this energy range are measured for the first time. New data are obtained for verification of theoretical models of nucleus–nucleus interactions.</p>