On the cation–\(\uppi \) interactions in 1,2-dihydro-1,2-azaborine

In recent years, it has become a strategy, and important area of research, to incorporate heteroatom into polycyclic aromatic compounds. Especially B/N containing aromatic compounds have been the topic of interest over the years, because of the isoelectronic nature of B–N bond with C=C bond. The substitution of B–N in place of C=C brings many important electronic and structural changes in the system. This work presents the investigation of the interaction between different cations and the $$\uppi $$ -cloud of the 1,2-dihydro-1,2-azaborine molecule using quantum chemical investigations at the MP2/aug-cc-pVDZ level of theory. The nature of interactions has been gauged by employing the energy decomposition analysis and molecular electron density critical point calculations. Further, the changes in N–H, B–H and C–H bond vibrational frequencies due to the cation binding were also investigated. Among the cations studied in this work, $$\hbox {Be}^{2+}$$ is found to provide the best compromise between size and charge as revealed by its high interaction energy and presence of electron density three critical points. SYNOPSIS. This work presents the investigation of the interaction between different cations and the $$\uppi $$ -cloud of the 1,2-dihydro-1,2-azaborine molecule at MP2/aug-cc-pVDZ level of theory. Among the cations studied in this work, $$\hbox {Be}^{2+}$$ is found to form the most stable complex and provides a best compromise between size and charge.