The Existence of a N→C Dative Bond in the C 60 -Piperidine Complex

The complexes formed between carbon allotropes (C , C fullerenes, graphene, and single-wall carbon nanotubes) and piperidine have been investigated by means of computational quantum chemical and experimental IR and NMR techniques. Alongside hydrogen bonds, the C⋅⋅⋅N tetrel bond, and lone-pair⋅⋅⋅π interactions, the unexpected N→C dative/covalent bond has been detected solely in complexes of fullerenes with piperidine. Non-planarity and five-member rings of carbon allotropes represent the key structural prerequisites for the unique formation of a dative N→C bond. The results of thermodynamics calculations, molecular dynamics simulations, and NMR and FTIR spectroscopy explain the specific interactions between C and piperidine. The differences in behavior of individual carbon allotropes in terms of dative bonding formation brings a new insight into their controllable organic functionalization.