On the Existence of N→C Dative Bond in C60-Piperidine Complex.

The complexes formed between carbon allotropes (C 20 , C 60 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. The effect of particular structural motives on the formation of dative bonds has been explored. 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 FT-IR spectroscopies explain the specific interactions between C 60 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.