Azadigermiridines by Addition of Diazomethane or Trimethylsilyldiazomethane to a Digermene1

Tetrakis(2,4,6-triisopropylphenyl)digermene ( 2 ), prepared by treatment of germanium bis(trimethylsilyl)amide with 2,4,6-triisopropylphenyllithium, reacts with diazomethane or trimethylsilyldiazomethane in a [2+1] fashion to furnish the N -methyleneamino-substituted azadigermiridines 7 and 8, respectively. The dissociation equilibrium between 2 and bis(triisopropylphenyl)germylene has been confirmed by the trapping reaction with a 1,2-quinone, from which the 1,3-dioxa-2-germaindan 10 was isolated. The structures of 2, 7, 8, and 10 were determined by X-ray crystallography. The sterically congested digermene 2 has a short Ge−Ge double-bond length of 2.213(1) Å.