[3,3'-Co(8-C5H10O-1,2-C2B9H10)(1',2'-C2B9H11)] (2) was synthesized by reaction of the caesium salt of [Co(C2B9H11)(2)](-) with dimethyl sulfate in the presence of sulfuric acid as catalyst and tetrahydropyrane as solvent; the zwitterionic compound (2) yielded[3,3'-Co(8-C4H4N-(CH2)(5)-O-1,2-C2B9H10)(1',2'-C2B9H11)](-) (6), [3,3'-Co(8-C8H6N-(CH2)(5)-O-1,2-C2B9H10)(1',2'-C2B9H11)](-) (7), and [3,3'-Co(8-C12H8N-(CH2)(5)-O-1,2-C2B9H10)-(1',2'-C2B9H11)](-) (8) through the nucleophilic addition of potassium pyrrolyl, indolyl and carbazolyl, respectively. The nucleophilic addition of the same salts on [3,3'-Co(8-C4H8O2-1,2-C2B9H10)(1',2'-C2B9H11)] (1) yielded, respectively, [3,3'-Co(8-C4H4N-(CH2)(2)-O-(CH2)(2)-O-1,2-C2B9H10)(1',2'-C2B9H11)](-) (3), [3,3'-Co(8-C8H6N-(CH2)(2)O-(CH2)2-O-1,2-C(2)B(9)H10)(1',2'-C2B9H11)](-) (4), and [3,3'-Co(8-C12H8N-(CH2)(2)-O-(CH2)(2)-O-1,2-C2B9H10)(1',2'C2B9H11)](-) (5). All these products were isolated, purified and characterized by means of H-1, H-1{B-11}, B-11, B-11{H-1} and C-13{H-1}-NMR and IR spectroscopies, MS MALDI-TOF spectrometry and elemental analysis. The behavior of the exo-cluster chain has been proven to be, in solution, very similar irrespective of the nucleophilic agent introduced into the molecule. The X-ray diffraction study of the potassium salt of 3 has proven the evidence of B-H ... K+ interactions in solid state. The H-1{B-11}-NMR spectra recorded in the range between 37degreesC and -58degreesC have proven the presence of the three intramolecular B-H ... K+ interactions in solution. The possible role of [Co(C2B9H11)(2)](-) as a doping agent in conducting organic polymers is also discussed.