A FREE CYCLOTRIGERMENIUM CATION WITH A 2-PI-ELECTRON SYSTEM

The reaction of tetrakis(tri-tert-butylsilyl)cyclotrigermene with trit yl tetraphenylborate in benzene produces tris(tri-teri-butylsilyl)cycl otrigermenium tetraphenylborate [(tert-Bu(3)SiGe)(3)(+)BPh(4)(-)], whi ch can be isolated as a yellow solid that is stable in the absence of air. The crystal structure of the cyclotrigermenium ion reveals a free germyl cation with a 2 pi-electron system. The three germanium atoms form an equilateral triangle similar to the carbon analog, the cyclopr openium ion.