Search for tetrylene structures that can exhibit catalytic activity: a quantum chemical approach

Abstract

We present the results of a quantum chemical study of a series of tetrylenes (silylenes, germylenes, and stannylenes), aimed at identifying structural and electronic factors affecting the width of the HOMO—LUMO energy gap. Compounds considered in this work contain atoms of Group 14 elements in both di- and tricoordinate states due to additional transannular interaction. They bear substituents bonded to the atom of the Group 14 element through atoms with and without lone electron pairs. It was found that tetrylenes stabilized by both additional transannular interaction and direct bonds between the atom of the Group 14 element and the heteroatom containing a lone electron pair (in this situation the ligand acts as n-donor) are characterized by wide HOMO—LUMO energy gaps, the gap in stannylenes always being narrower than in the related silylenes and germylenes. Localization of the HOMO and LUMO in certain tetrylenes is analyzed.