In a study by Chianese et al , it was proposed that the extrinsic aromatic stabilization energy of benzene arises from favourable σ-framework interactions. Building on this concept, norbornane bicyclic compounds like quadricyclane (QC) and [2.2.1]propellane (PPL) can be considered saturated counterparts of a conjugated π system. This suggests that the strain present in these molecules contributes to stability through favourable σ-bond interactions, akin to the aromatic stabilization observed in benzene. These insights underscore the correlation between chemical shifts observed in C-NMR and C1s XPS binding energies. The deshielding observed in unsaturated carbons and the shielding effects observed in saturated and bridge carbons collectively contribute to the observed trends, providing valuable insights into the chemical reactivity and stability of norbornyl derivatives.