Comparative Theoretical Study on the Reactivity of Digermenes and Disilenes in Addition Reactions

Abstract

Density functional theory (DFT) calculations at the M06-2X/6-311+G(3df,2p) level were carried out to study the mechanism, potential energy surface and substituent effect of the addition reactions of H2O toward digermenes. For comparison, the addition reactions of disilenes with H2O were also investigated. The computed results show that addition reactions related to the H2O trimer are kinetically more favorable than those involving H2O monomer or dimer for the same parent substrate. The electron-withdrawing groups at Ge atom of Ge=Ge double bond facilitate the progress of the addition reaction, while electron-donating substituents have the opposite effects. H2Ge=GeH2 ((SiMe3)2Ge=Ge(SiMe3)2) is less reactive than H2Si=SiH2 ((SiMe3)2Si=Si(SiMe3)2) in the addition reactions with H2O.