Lithium tetramethylphospholide, complexes

The half-sandwich and sandwich complexes of phospholides and phosphole tetramer are known even for the nontransition metals. The half-sandwich arrangement was studied for lithium tetramethylphospholide [89AG(E)1367] and sodium derivative 127 generated from the phospholide tetramer and sodium in the presence of 1,2-dimethoxyethane [94JA3306 96AG(E)1125]. Potassium and 1,2-dimethoxyethane in THE in these conditions give a full dianionic sandwich 128. 

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