ic026033s_si_002.pdf (39.12 kB)
Electron Deficient Bridges Involving Silylenes: A Theoretical Study
journal contribution
posted on 2003-06-25, 00:00 authored by Prasad V. Bharatam, Rajnish Moudgil, Damanjit KaurAb initio and density functional studies show that silylenes can form complexes with BH3 and the resultant complexes
possess 3c−2e bridges. The complexation energy for the formation of the these H-bridged structures is in the
range of 18−46 kcal/mol. The characteristics of the electron deficient bridges depend on the substituents attached
to the silylenes. With an increase in the π-donating capacity of the substituents, the exothermicity of complex
formation gets reduced but the kinetic stability of the H-bridged structures increase. The natural bond orbital analysis
shows that all the H-bridged structures are associated with σB-H→pπSi second-order delocalization, which is
responsible for the origin of the 3c−2e bonds. The complexation energies of the silylene−BH3 complexes have
been shown to have a correlation to the singlet−triplet energy gaps of silylenes.