Synthesis and structure of a carbamato-bridgded digallyl-ferrocenophane - Fixation of carbon dioxide with aminogallanes

By reaction of tmp(2)GaCl (tmp = 2,2,6,6-tetramethylpiperidino) (1) with dilithioferrocene the 1,1'-digally1ferrocene [{Fe(eta(5)-C5H4)(2)}t(tmp(2)Ga)(2)] (2) was prepared. 2 reacted with CO, to afford the ferrocenophane [F{eta(5)-C5H4-Ga(O(2)Ctmp-)(mu(2)-O(2)Ctmp)}(2)](3). Here, an eight-membered Ga(OCO)(2)Ga-Ring is the bridge in the ferrocenophane structure. The gallium carbamates [Me(2)GaO(2)Ctmp](2) (5), and tmp(2)Ga(eta(2)-O(2)Ctmp) (7) show Structural features embedded in 3. The compounds were fully characterized by NMR, cyclovoltammetry and single crystal X-ray structure analysis.