How Reasons for Entry into the Profession Illuminate Teacher Identity Development

Aminosilylene, comprising reactive NH- and Si (II) sites next to each other, is an intriguing class of compounds due to its ability to show diverse reactivity. However, stabilizing the reactive NH- group next to the free Si (II) atom is challenging and has not yet been achieved. Herein, we report the first examples of base stabilized free aminosilylenes Ar*NHSi (PhC (Nt Bu) 2) (1 a) and Mes*NHSi (PhC (Nt Bu) 2) (1 b) (Ar*=2, 6-dibenzhydryl-4-methylphenyl and Mes*=2, 4, 6-tri-tert-butylphenyl), tolerating a NH- group next to the naked Si (II) atom. Remarkably, 1 a and 1 b exhibited interesting differences in their reactivity upon heating. With 1 a, an intramolecular C (sp3) -H activation of one of the benzhydryl methine hydrogen atoms to the Si (II) atom produced the five-membered cyclic silazane 2. However, with 1 b, a rare 1, 2-hydrogen shift to the Si (II) atom afforded a silanimine 3, with a hydride ligand attached to an unsaturated silicon atom. Further, the coordination capabilities of 1 a were also tested with Ru (II) and Fe (0) precursors. Treatments of 1 a with Ru (η6 -p-cymene) Cl2 2 led to the isolation of a η6 -arene tethered complex RuCl2 Ar*NHSi (PhC (t BuN) 2) -κ1 -Si-η6 -arene (4), whereas with the Fe (CO) 5 precursor a Fe (0) complex Fe (CO) 4 Ar*NHSi (PhC (t BuN) 2) -κ1 -Si (5) was obtained. Density functional theory (DFT) calculations were conducted to shed light on the structural, bonding, and energetic aspects in 1-5.