Coordination of Donor-Functionalized Cyclopentadienyl Ligands at Platinum(II) Centers: Syntheses and Molecular Structure of [μ-(1,2- η2:5,6-η2-cod){(η5-C5Me4CH2CH2NMe2)MePt}2]

The syntheses of novel monomeric and dimeric platinum(II) complexes are reported. Modified cyclopentadienyls (Cp R ) such as pentamethylcyclopentadienyl (Cp*) and its functionalized derivatives 1-[2-(dimethylamino)eth-1-yl]-2,3,4,5-tetramethylcyclopentadienyl (Cp* N ), 1-(but-3-en-1-yl)-2,3,4,5-tetramethylcyclopentadienyl (Cp* 2 = ) and 1-(pent-4-en-1-yl)-2,3,4,5-tetramethylcyclopentadienyl (Cp* 3 = ) were reacted with [( η 4 -cod)PtMeX] (COD = cis, cis -1,5-cyclooctadiene, X = halogen) to give the monomeric species [(1,2- η 2:5,6-cod)( η 5 -Cp R )MePt] (Cp R = Cp* ( 1 ), Cp* N ( 3 ), Cp* 2 = ( 5 ), Cp* 3 = ( 6 )), wherein the COD ligand is η 2 -coordinated to one metal center. Dimerization of 1 or 3 resulted in the COD-bridged species [ μ -(1,2- η 2:5,6- η 2 -cod){( η 5 -Cp R )MePt} 2 ] ( 2, 4 ); the molecular structure of 4 was determined by single-crystal X-ray diffraction. All new compounds were characterized by 1 H, 13 C, and 195 Pt NMR spectroscopy and by elemental analysis where possible.