Tetrakis cyclotrigermenes

It should also be noted here that recent work in Japan has shown that a free germanium cation can be prepared and structurally characterized. Thus, the reaction of tetrakis (tri-z-butylsilyl)cyclotrigermene with trityl tetraphenylborate affords (t-Bu3SiGe)3+ BPI14 as a yellow crystalline solid. X-ray crystallography shows that there is no close interaction between the anion and the cation. The stability of the compound is presumably due not only to the steric protection afforded by the bulky t-BtcSi substituents, but also to the fact that it contains a 2jr-electron aromatic ring.198... 

Cyclotrigermenes were obtained from the reaction of metal-14 anions with tris(tri-r-butylsilyl)cyclotrigermenium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, the TFPB behaving as the leaving group (equation 156)168. The cyclotrigermene structure was established by X-ray determination. 

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