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A study of the strong N−X⋅⋅⋅⁻O−N⁺ (X=I, Br) halogen bonding interactions reports 2×27 donor×acceptor complexes of N‐halosaccharins and pyridine N‐oxides (PyNO). DFT calculations were used to investigate the X⋅⋅⋅O halogen bond (XB) interaction energies in 54 complexes. A simplified computationally fast electrostatic model was developed for predicting the X⋅⋅⋅O XBs. The XB interaction energies vary from −47.5 to −120.3 kJ mol⁻¹; the strongest N−I⋅⋅⋅⁻O−N⁺ XBs approaching those of 3‐center‐4‐electron [N−I−N]⁺ halogen‐bonded systems (ca. 160 kJ mol⁻¹). ¹H NMR association constants (K_XB) determined in CDCl₃ and [D₆]acetone vary from 2.0×10⁰ to >10⁸ m⁻¹ and correlate well with the calculated donor×acceptor complexation enthalpies found between −38.4 and −77.5 kJ mol⁻¹. In X‐ray crystal structures, the N‐iodosaccharin‐PyNO complexes manifest short interaction ratios (R …