1-(3'-Amino)propylsilatrane (I) and 1-(3'-acetaniido)propylsilatrane (H) react with anhydrous cobalt(II) chloride to give dichlorobis[1-(3'-amino)propylsilatrane]cobalt(II) {Co[NH2CH2CH2CH2Si(OCH2CH2)(3)N](2)Cl-2} (M) and dichlorobis[1-(3'-acetamido)propylsilatrane]cobalt(II) {Co[CH3C(O)NHCH2CH2CHSi(OCH2CHI-)(3)N](2)Cl-2} (IV). Being unstable, compound IV transforms into an iniidic acid derivative. Reactions of silatranes I and H with dicobalt octacarbonyl afford hexakis{1-(3'-aminoamido)propylsilatrane}cobalt(II) bis(tetracarbonylcobaltate) {Co[NH2CH2CHCHSi(OCH2CH2)(3)N](4.8)[HC(O)NHCH2CH2CH,Si(OCH2CH2)(3)N](1.2)}[CO(CO)(4)](2) (V) and hexakis[1-(3'-acetamido)propylsilatrane]cobalt(II) bis(tetracarbonylcobaltate) {Co[CH3C(O)NHCH2CH2CH2Si(OCH2CH2)(3)N](6)} [CO(CO)(4)](2) (VI), respectively. In acetonitrile, tetracarbonylcobaltate anions of compound VI are oxidized with atmospheric oxygen and moisture to cobalt hydroxocarbonate, giving a carbonate gel (VII).