1-Isothiocyanatosilatrane Derived from Asymmetric Tetradentate Ligand: Synthesis, Structural Analyses, Reactivity, and Computational Studies

1-Isothiocyanatosilatrane N[(CH2(Me2C6H2O))(2)(CH2CH2O)]SiNCS was synthesized from the asymmetric tetradentate ligand N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-2-aminoethanol in appreciable yield by in situ reaction of its 1-chlorosilatrane counterpart with potassium thiocyanate. The 1-isothiocyanatosilatrane was structurally characterized by elemental analysis, FTIR spectroscopy, multinuclear NMR (H-1 and C-13), thermogravimetric analysis, and mass spectrometry. The title silatrane when subjected to reactivity studies with Lewis bases and acids, yielded the corresponding adducts, which were characterized by elemental analysis and spectroscopic techniques. Computational studies were performed to analyze the effect of the asymmetric silatrane ring environment on the NSi transannular bond length and consequently on the potentially reactive Si-NCS centre.