Activation of cyclopentadiene derivatives by an α-diimine-ligated Mg-Mg-bonded compound.

Heteroleptic, bimetallic (Mg/K) cyclopentadienyl complexes (2-4) were synthesized by the reaction of the Mg-Mg-bonded compound [K(THF) 3 ] 2 [LMg-MgL] (1, L = [(2,6-iPr 2 C 6 H 3 )NC(CH 3 )] 2 2- ) with cyclopentadiene derivatives, 6,6-dimethylfulvene, 6-(dimethylamino)fulvene, or 1,2,3,4-tetramethyl-1,3-cyclopentadiene. The reactions proceed through diverse pathways, including hydrogen abstraction, C-C coupling, and dehydrogenation, depending on the property of the polyene substrate, thus providing an access to alkali/alkaline earth metal cyclopentadienyl complexes.