Abstract: This paper deals with the reaction of binary polyhedral borane anion quaternary ammonium salts B_nH_n^2- (in which n is 10 or 12) and tetraethyl-ammonium octahydrotriborate B₃H₈^- with (ferrocenylmethyl) N-alkyl-N,N-dimethylammonium halide C₅H₅FeC₅H₄CH₂N (R) Me₂X (in which Ris CH₃—, C₂H₅—, n-C₃H₇—, CH₃=CHCH₂— or CH = CCH₂—, respectively) and 1,1'-bis-(N-alkyl-N, N-dimethylaminomethyl) ferrocene dihalide Fe(C₅H₄CH₂-N (R) Me₂X)₂ (in which Ris CH₃—, C₂H₅—, n-C₃H₇—, CH₂=CHCH₂ and CH = CCH₂— respectively), and with the effect of ratios of reactants on products. In each of the reactions, irrespective of the ratios of the reactants, only one product is obtained (in good yields 90.2—98.5%). Apparently, the above mentioned experimental results were explained by the HSABprinciple. 30 new compounds have been synthesized and characterized (their physical properties,IRspectra, yields and analysis data are given). All these compounds are stable to hydrolysis.