Small Cycloalkane (CN) 2 CC(CN) 2 Structures Are Highly Directional Non‐covalent Carbon‐Bond Donors

High‐level calculations (RI‐MP2/def2‐TZVP) disclosed that the σ‐hole in between two C atoms of cycloalkane X 2 CCX 2 structures (X=F, CN) is increasingly exposed with decreasing ring size. The interacting energy of complexes of F − , HO − , N≡C − , and H 2 CO with cyclopropane and cyclobutane X 2 CCX 2 derivatives was calculated. For X=F, these energies are small to positive, while for X=CN they are all negative, ranging from −6.8 to −42.3 kcal mol −1 . These finding are corroborated by a thorough statistical survey of the Cambridge Structural Database (CSD). No clear evidence could be found in support of non‐covalent carbon bonding between electron‐rich atoms (El.R.) and F 2 CCF 2 structures. In marked contrast, El.R.⋅⋅⋅(CN) 2 CC(CN) 2 interactions are abundant and highly directional. Based on these findings, the hydrophobic electrophilic bowl formed by 1,1′,2,2′‐tetracyano cyclopropane or cyclobutane derivatives is proposed as a new and synthetically accessible supramolecular synthon.