Digermane was prepared in approximately 50% yield by a new coupling reaction between potassium germyl and chlorogermane in the absence of a solvent. The disproportionation reactions of digermane were studied and compared to those of disilane and the alkyldisilanes. The products of the reaction between lithium chloride or lithium deuteride and digermane are germane and a polymer. The relative rates (Si₂H₆ > Ge₂H₆ > alkyldisilanes) are explained by electron density effects on nucleophilic substitution. The results of the potassium hydride-digermane reaction suggest a one step reaction that produces germane and potassium germyl. The germane produced is found to react with the excess potassium hydride by a deprotonation reaction to yield potassium germyl and hydrogen. The relative rates for reaction with KH (Ge₂H₆ > Si₂H₆ > alkyldisilanes) are explained by the simplicity of the digermane reaction compared to the complex silene mechanism proposed for the disilane reaction.
