Synthesis and Reactivity of Acyclic Germanimines: Silyl Rearrangement and Cycloadditions

We report the synthesis of aromatic germanimines [(HMDS)(2)Ge=NAr] (Ar = Ph, Mes, Dipp; Mes = 2,4,6-Me3C6H2, Dipp = 2,6-iPr(2)C(6)H(3)) and an investigation into their associated reactivity. [(HMDS)(2)Ge=NPh] decomposes above -30 degrees C, while [(HMDS)(2)Ge=NDipp] engages in an intramolecular reaction at 60 degrees C. [(HMDS)(2)Ge=NMes] was shown to rearrange via a 1,3-silyl migration to give [(HMDS){(SiMe3)-(Mes)N}Ge(NSiMe3)] in a 1:7 equilibrium mixture at room temperature. These latter germanimines react with unsaturated polar substrates such as CO2, ketones, and arylisocyanate via a [2 + 2] cycloaddition pathway.

Automated summary

This study reports the synthesis and reactivity of aromatic germanimines, demonstrating their decomposition and intramolecular reactions at different temperatures. Furthermore, it shows that these germanimines can react with various unsaturated polar substrates via a [2 + 2] cycloaddition pathway.