A study on the aromaticity and magnetotropicity of 10π-electron azapentalene derivatives

► Topological resonance energy was used to examine the aromaticity of 3a-azapentalenes. ► The local aromaticity was studied using circuit resonance energy and ring current (RC) methods. ► The RC values were compared with the nucleus-independent chemical shift values. ► We have identified a local aromaticity difference between the two five-membered rings.