Synthesis and Structure of Tin and Germanium Complexes as Precursors Containing Alkoxyaminoalkoxide Ligands for Thin Film Transistors

This paper describes the preparation of four novel Sn and Ge complexes containing alkoxyaminoalkoxide type ligands {L1H = 1-[methoxy(methyl)amino]-2-methylpropan-2-ol; L2H = 1-[methoxy(methyl)amino]-2-methylbutan-2-ol} for potential use as precursors for thin film transistors. All compounds were prepared at room temperature by stirring a solution containing Sn(btsa)₂ [btsa = bis(trimethylsilyl)amide] or Ge(btsa)₂ with two equivalents of L1H or L2H to form Sn(L1)₂ (1), Sn(L2)₂ (2), Ge(L1)₂ (3) and Ge(L2)₂ (4). All of the complexes were characterized by NMR and FTIR spectroscopy as well as elemental and thermogravimetric analyses. When the more symmetric and compact ligand L1H was applied, solid products 1 and 3 were generated and their structures were studied using X-ray diffraction. Applying the strategy of ligand design at the molecular level, the symmetric ligand was changed to an asymmetric one, replacing one of the two neighboring methyl groups of the amino alcohol group with an ethyl group, and forming liquid complexes 2 and 4 for both metals.