The addition of oxygen to tetramesityldigermene

The addition of atmospheric oxygen to tetramesityldigermene under a variety of conditions was studied. The addition of oxygen to the digermene, prepared by the photolysis of hexamesitylcyclotrigermane in THF, cleanly afforded 3,3,4,4-tetramesityl-3,4-digermadioxetane (7). The photolysis of hexamesitylcyclotrigermane in toluene in the presence of triethylsilane under the ambient atmosphere gave a very complex product mixture, from which 2,2,4,4-tetramesityl-2,4-digermadioxetane (9), tetramesityldigermaoxirane (10) and 2,2,4,4,5,5-hexamesityl-2,4,5-trigermadioxolane (11) were isolated and identified. The structures of compounds 9 and 11 were determined by X-ray crystallography.