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Abstract London dispersion (LD) interactions, which stem from long‐range electron correlations arising from instantaneously induced dipoles can occur between neighboring atoms or molecules, for example, between H atoms within ligand C−H groups. These interactions are currently of interest as a new method of stabilizing long bonds and species with unusual oxidation states. They can also limit reactivity by installing LD enhanced groups into organic frameworks or ligand substituents. Here, we address the most recent advances in the design of LD enhanced ligands, the sterically counterintuitive structures that can be generated and the consequences that these interactions can have on the structures and reactivity of sterically crowded heavy group 14 species. 

Thermal Sn–C cleavage in the diarylstannylene Sn(Ar^iPr4)₂(Ar^iPr4= C₆H₃-2,6-(C₆H₃-2,6-iPr₂)₂) was used to generate ˙Sn(Ar^iPr4) and ˙Ar^iPr4radicals for alkyne arylstannylation. 

We report the reactivity of NH₃with ferrioplumbyl- and ferriostannylene complexes. DFT analysis of the Sn system describes a mechanism of reactivity and X-ray analysis shows a long Sn–N bond, giving a structural snapshot into its reversible nature. 

Structural characterization of the complex [B(β-pinane) 3 ] (1) reveals non-covalent H⋯H contacts that are consistent with the generation of London dispersion energies involving the β-pinane ligand frameworks. The homolytic fragmentations of 1 , and camphane and sabinane analogues ([B(camphane) 3 ] (2) and [B(sabinane) 3 ] (3)) were studied computationally. Isodesmic exchange results showed that London dispersion interactions are highly dependent on the terpene's stereochemistry, with the β-pinane framework providing the greatest dispersion free energy (Δ G = −7.9 kcal mol −1 ) with Grimme's dispersion correction (D3BJ) employed. PMe 3 was used to coordinate to [B(β-pinane) 3 ], giving the complex [Me 3 P–B(β-pinane) 3 ] ( 4 ), which displayed a dynamic coordination equilibrium in solution. The association process was found to be slightly endergonic at 302 K (Δ G = +0.29 kcal mol −1 ).