10.1021/ic101485a.s002 S. M. Ibrahim Al-Rafia S. M. Ibrahim Al-Rafia Paul A. Lummis Paul A. Lummis Michael J. Ferguson Michael J. Ferguson Robert McDonald Robert McDonald Eric Rivard Eric Rivard Low-Coordinate Germylene and Stannylene Heterocycles featuring Sterically Tunable Bis(amido)silyl Ligands American Chemical Society 2010 iPr 2C 2Si group 14 centers chalcogen sources sulfido complexes steric protection dimeric oxo SiPh Structural analyses S 8 3NO Stannylene Heterocycles metallylene steric bulk Dipp group NSiN chelate 2010-10-18 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Low_Coordinate_Germylene_and_Stannylene_Heterocycles_featuring_Sterically_Tunable_Bis_amido_silyl_Ligands/2721085 A series of monomeric heterocyclic metallylenes [{<sup><i>i</i></sup>Pr<sub>2</sub>Si(NR)<sub>2</sub>}M:] (M = Ge and Sn; R = Dipp = 2,6-<i><sup>i</sup></i>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub> or SiPh<sub>3</sub>) have been prepared. Preliminary atom-transfer chemistry involving the new low-valent germylenes with the chalcogen sources Me<sub>3</sub>NO and S<sub>8</sub> yielded the corresponding dimeric oxo- and sulfido complexes (e.g., [{<i><sup>i</sup></i>Pr<sub>2</sub>Si(NDipp)<sub>2</sub>}Ge(μ-E)]<sub>2</sub>; E = O and S). Structural analyses of the metallylenes and their oxidized products reveal that incorporation of the umbrella-shaped triarylsilyl groups (SiPh<sub>3</sub>) within the NSiN chelate confers additional steric protection about the group 14 centers relative to a Dipp group. The inclusion of sterically modifiable −SiAr<sub>3</sub> (Ar = aryl) units as part of a bis(amido) ligand array represents a new approach in this field and holds considerable promise with regard to attaining increasingly higher degrees of steric bulk.