Bis(trimesitylgermylcarbodiimido)germylene, trimesitylgermylcyanamide and trimesitylgermylcarbodiimide

Bis(trimesitylgermylcarbodiimido)germylene (1), isolated as a white precipi tate from the reaction of lithium trimesitylgermylcyananide with dichloroge rmylene, is stable at room temperature in the absence of water and oxygen. The germylene structure is preserved in the reaction with 3,5-di-t-butylcat echol, while subsequent addition to 3,5-di-t-butylorthoquinone gave the cor responding spirogermane. Thermal decomposition of 1 occurs around 50 degree s C leading to bis(trimesitylgermyl)carbodiimide and polycarbodiimidogermyl ene. Hydrolysis of 1 gave the corresponding monogermylated derivative of cy an amide (3) in two isomeric forms: trimesitylgermylcyanamide (3a) and trim esitylgermylcarbodimide (3b), in equilibrium in solution. Isomer 3b is the first compound to precipitate from a benzene solution. Its structure was es tablished by X-ray diffraction. Compound 3 decomposes on heating to form di cyanamide and bis(trimesitylgermyl)carbodiimide. (C) 2000 Elsevier Science S.A. All rights reserved.