Isolation and Reactivity of Silepins with a Sterically Demanding Silyl Ligand.

Silacycloheptatriene (silepin) species are novel silicon compounds reported in recent years. The interplay between the "closed" silepin and the "open" silylene form enables an enhanced stability of the low valent species while maintaining a high reactivity towards small molecules. In this work, two new silepins of similar structures to literature known compounds bearing modified silyl ligands are reported. A unique intramolecular activation of an aromatic hydrogen is found, and the respective formed hydrosilanes are characterized. We further synthesized iron(0) carbonyl complexes of known and new silepins in order to investigate their electronic properties relative to each other to gain more insight into substitution effect in such compounds. [ABSTRACT FROM AUTHOR]