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Updated: Jul 18, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Theoretical studies on NMR chemical shifts in azacubanes
Rahul V Pinjari1, Nilesh R Dhumal, Shridhar P Gejji
1Department of Chemistry, University of Pune, Pune 411007, India.
Abstract:
Successive substitution of CH groups of cubane (CH)(8), by isoelectronic nitrogen atoms leads to a class of energy-rich azacubanes (CH)(8-alpha)N(alpha) (with alpha=1-8). In the present work, we systematically investigate how substitution of nitrogen in a cubanoid influence deshielding of carbon and manifest in the chemical shift in NMR spectra calculated using the second order Møller-Plesset (MP2) perturbation level of theory. PMR spectra predict a large downshift of delta(H)=7.9 ppm in heptaazacubane owing to the more number of nitrogen and the stronger C-H...N interactions. These chemical shifts are explained by the net atomic charges derived from the population analysis based on Hirshfeld partitioning scheme.
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