The Synthesis and Crystal Structure of Alkenyl-Substituted Cyclopentadienyl Ruthenium Complexes

Two alkenyl-substituted cyclopentadienyl ruthenium complexes(1,2) were synthesized. The diallylcyclopentadiene was obtained by a one-pot reaction of sodium cyclopentadienide and allyl chloride. The complex(2) with this ligand is chiral and characterized by X-ray analysis. It belongs to the triclinic space group P1 ( #2) with a = 1.1257(6) nm, b = 1. 8525(7)nm, c = 1.0134(4)nm, α =90. 89 (3)°,β= 102.77(4)°, γ=106.93(3)°. V= 1.964(1)nm3, Z = 2, Dcalc= 1.363g·cm-3, F(000) = 832. 00. The X-ray structure of complex (2) reveals that geometry around the ruthenium can be considered as distorted tetrahedral. The distance of Ru-C, Ru-P and Ru-Cl is greatly different from that in CpRu (PPh3 )2Cl. It can be concluded that the introduction of diallyl group into the cyclopentadienyl ligand results in the redistribution of electron around the ruthenium. The donation from diallyl group to cyclopentadienyl ligand weakens the back-donation from ruthenium to cyclopentadienyl ligand. Hence, the electron is transferred to PPh3, Cl ligands.