Nucleophilicity of the boron atom in compounds R-B, (R = F, Cl, Br, I, CN, NC, CH3, SiH3, CF3, H): a new look at the inductive effects of the group R

• Main Authors: Alkorta, I. (Author), Legon, A. (Author)
• Format: Article
• Language: English
• Published: Royal Society of Chemistry 2022
• Online Access: View Fulltext in Publisher

 Nucleophilicities NR-B of molecules R-B (R = F, Cl, Br, I, CN, NC, CH3, SiH3, CF3, H) are determined from the equilibrium dissociation energies De of 70 hydrogen-bonded complexes R-B⋯HX (X = F, Cl, Br, I, HCN. HCCH, HCP). The change in NR-B relative to NH-B of H-B allows a quantitative measure of the inductive effect IR of each group R because only the group R affects the electron density associated with the axial non-bonding electron pair carried by the boron in R-B. An alternative definition of IR, suggested by the strong correlation of the NR-B values with the minimum value σmin of the molecular electrostatic surface potential on the 0.001 e Bohr−3 iso-surface along the R-B axis leads to excellent agreement between the two definitions. © 2022 The Royal Society of Chemistry.