Hydrogermolysis reactions involving the alpha-germylated nitriles R3GeCH2CN (R = ph, Pr-i, Bu-t) and germanium amides R3GeNMe2 (R = Pr-i, Bu-t) with Ph3GeH: substituent-dependent reactivity and crystal structures of (Pr3GeGePh3)-Ge-i and (Bu3Ge)-Ge-t

摘要

The alpha-germylated nitriles R3GeCH2CN ( R = Ph, Pr-i, Bu-t) and germanium amides R3GeNMe2 (R = Pr-i and Bu-t) have been prepared and characterized and their reactivity with Ph3GeH in CH3CN has been explored to investigate their utility for the construction of Ge-Ge bonds. In each case the phenyl and iso-propyl derivatives furnish the corresponding digermanes R3GeGePh3 (R = Ph, Pr-i) where the amide reagents are converted to R3GeCH2CN in situ which subsequently react with Ph3GeH. The rate of the Ge-C bond cleavage reactions was found to depend on the steric and electronic properties of the organic substituents. Attempted synthesis of (Bu3GeGePh3)-Ge-t by these methods did not result in the desired product but rather in isolation of the 3-amidocrotononitrile species (Bu3Ge)-Ge-t[NHC(CH3)CHCN]. The crystal structures of (Pr3GeGePh3)-Ge-i and (Bu3Ge)-Ge-t[NHC(CH3)CHCN] have been determined. (C) 2008 Elsevier B. V. All rights reserved.