Unraveling the Amine‐Induced Disproportionation Reaction of Perchlorinated Silanes—A DFT Study

Abstract

AbstractA detailed quantum‐chemical study on the amine‐induced disproportionation reaction of perchlorinated silanes toneo‐Si5Cl12is reported. The key intermediate in the resulting mechanistic scenario is a dichlorosilylene amine adduct, which is in tune with recent experimental findings. Yet, at variance with the generally accepted notion of silicon‐chain growth by concerted silylene insertion into Si−Cl bonds of lower silanes, the formation ofneo‐Si5Cl12follows more complex pathways. The reactivity is dominated by the Lewis–base character of the dichlorosilylene amine adduct and characterized by three elementary steps that bear close resemblance to the key elementary steps identified earlier for the chloride‐induced disproportionation of Si2Cl6. NBO and QTAIM analyses of the key reactive species SiCl2⋅NMe3and SiCl3−provide a rationale for these striking similarities.