Monomeric lithium triazapentadienyl complexes

Abstract

Treatment of 1,3,5-triazapentadienes [N{(C₃F₇)C(Mes)N}₂]H and [N{(C₃F₇)C(Dipp)N}₂]H (where Mes = 2,4,6-Me₃C₆H₂; Dipp = 2,6-Prⁱ₂C₆H₃) with n-BuLi in hexane, followed by the crystallization from hexane–THF mixture afforded the corresponding lithium 1,3,5-triazapentadienyl complexes as their THF solvates. X-Ray crystallographic analyses revealed that [N{(C₃F₇)C(Mes)N}₂]Li(THF)₂ and [N{(C₃F₇)C(Dipp)N}₂]Li(THF) are monomeric in the solid state. [N{(C₃F₇)C(Mes)N}₂]Li(THF)₂ has a four-coordinate lithium center with a distorted tetrahedral geometry, and features a boat-shaped C₂N₃Li metallacycle. [N{(C₃F₇)C(Dipp)N}₂]Li(THF) has a three-coordinate lithium atom and a planar, U-shaped C₂N₃ ligand backbone. The synthesis, solid-state structure, and ¹H and ¹⁹F NMR spectroscopic details of [N{(C₃F₇)C(Mes)N}₂]H are also reported.