An NHC-Stabilized H₂ GeBH₂ Precursor for the Preparation of Cationic Group 13/14/15 Hydride Chains

The synthesis, characterization and reactivity studies of the NHC-stabilized complex IDipp ⋅ GeH₂ BH₂ OTf (1) (IDipp=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) are reported. Nucleophilic substitution of the triflate (OTf) group in 1 by phosphine or arsine donors provides access to the cationic group 13/14/15 chains [IDipp ⋅ GeH₂ BH₂ ERR¹ R² ]⁺ (2 E=P; R, R¹ =H; R² =^t Bu; 3 E=P; R=H; R¹ , R² =Ph; 4 a E=P; R, R¹ , R² =Ph; 4 b E=As; R, R¹ , R² =Ph). These novel cationic chains were characterized by X-ray crystallography, NMR spectroscopy and mass spectrometry. Moreover, the formation of the parent complexes [IDipp ⋅ GeH₂ BH₂ PH₃ ][OTf] (5) and [IDipp ⋅ GeH₃ ][OTf] (6) were achieved by reaction of 1 with PH₃ . Accompanying DFT computations give insight into the stability of the formed chains with respect to their decomposition.