DFT studies on the insertion reactions of silylenoid into Si-X bonds (XÂ =Â F, Cl, Br)

The insertion reactions of the silylenoid H2SiLiF into Si-X bonds (X = F, Cl, Br) have been studied by ab initio and DFT calculations. The results indicate that the insertions proceed in a concerted manner, forming H2SiXCH3 and LiF. The essence of these reactions are the donations of the electrons of X into the p orbital on the Si atom in H2SiLiF and the σ electrons on the Si atom in H2SiLiF to the positive SiH3 group. The order of reactivity by H2SiLiF insertion indicates the reaction barriers increase for the same-family element X from top down in the periodic table. All the insertions are exothermic reactions.