A convenient route to mixed cationic group 13/14/15 compounds

The formation of novel cationic mixed main group compounds is reported revealing a chain composed of different elements of group 13, 14, and 15. Reactions of different pnictogenylboranes R 2 EBH 2 ·NMe 3 (E = P, R = Ph, H; E = As, R = Ph, H) with the NHC-stabilized compound IDipp·GeH 2 BH 2 OTf ( 1 ) (IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene) were carried out, yielding the novel cationic, mixed group 13/14/15 compounds [IDipp·GeH 2 BH 2 ER 2 BH 2 ·NMe 3 ] + ( 2a E = P; R = Ph; 2b E = As; R = Ph; 3a E = P; R = H; 3b E = As; R = H) by the nucleophilic substitution of the triflate (OTf) group. The products were analysed by NMR spectroscopy and mass spectrometry and for 2a and 2b also by X-ray structure analysis. Further reactions of 1 with H 2 EBH 2 ·IDipp (E = P, As) resulted in the unprecedented parent complexes [IDipp·GeH 2 BH 2 EH 2 BH 2 ·IDipp][OTf] ( 5a E = P; 5b E = As), which were studied by X-ray structure analysis, NMR spectroscopy and mass spectrometry. Accompanying DFT computations give insight into the stability of the formed products with respect to their decomposition. Reactivity studies on the complex IDipp·GeH 2 BH 2 OTf with different pnictogenylboranes were carried out. Hereby, unprecedented cationic group 13/14/15 compounds containing chains of only hydrogen-substituted 13/14/15 elements could be obtained.