A family of group 4 permethylpentalene complexes, Pn*MCpRX (M = Ti, Zr; CpR = Cp, CpMe, CptBu, CpnBu, CpMe3, Ind; X = Cl, Me) has been synthesised and fully characterised by multinuclear NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction studies. The effect of substitution around the Cp ligand was examined for ethylene polymerisation

A series of group 4 complexes η5-Pn*(H)TiCl3, [η5-Pn*(H)ZrCl3]2 and [η5-Pn*(H)HfCl3]2 containing a η5-permethylpentalene ligand were prepared by the reaction of η5-Pn*(H)SnMe3 with the corresponding group 4 starting materials. The complexes inititiated ring opening polymerisation of L- and rac-lactide.


We describe the synthesis, structure and bonding of the first iridium and rhodium permethylpentalene complexes, syn-[M(CO)2]2(μ:η55-Pn*) (M = Rh, Ir). In fact, [Ir(CO)2]2(μ:η55-Pn*) is the first iridium pentalene complex. The novel 14 electron species η8-Pn*TiR2 (Pn* = C8Me6; R = Me, CH2Ph) have been synthesised and spectroscopically and structurally characterised. Subsequent reaction with CO2 leads to the activation and double insertion of CO2 into both Ti–alkyl bonds to form the electronically saturated η8-Pn*Ti(κ2-O2CR)2 (R = Me, CH2Ph) complexes.

We report a series of anti-bimetallic transition metal complexes based on the permethylpentanyl (Pn*, C8Me6) ligand: anti-(MCpR5)2Pn* (where M = Fe, Co and Ni and R = H or Me). All anti-(MCpR5)Pn* structures have diamagnetic ground states. 


Recent publications:

Synthesis, characterisation and redox properties of anti-bimetallic permethylpentalene complexes, S. Binding,J.C.Green, Z.R.Turner, J-C.Buffet, D.O'Hare, DaltonTrans., (2019), 48, 4263-4273.

Synthesis, characterisation and redox properties of anti-bimetallic permethylpentalene complexes, S. Binding, J.C. Green, Z.R. Turner, J-C. Buffet, D. O'Hare, Dalton Trans., (2019),  48, 4263-4273. 

Synthesis and characterization of permethylpentalene titanium aryloxide and alkoxide complexes, D.D. Clement, S.C. Binding, T.A.Q. Arnold, F.M. Chadwick, I.J. Casely, Z.R. Turner, J-C. Buffet, D. O'Hare, Polyhedron, (2019), 157, 146-151. 

Titanium and Zirconium Permethylpentalene Complexes, Pn*MCpRX, as Ethylene Polymerization Catalysts, D. A. X. Fraser, Z. R. Turner, J.-C. Buffet and D. O’Hare, Organometallics, (2016), 35, 2664-2674.

Zirconium and Hafnium Permethylpentalene Compounds, F. M. Chadwick, R. T. Cooper and D. O’Hare, Organometallics, (2016), 35, 2092-2100.

Group 9 Bimetallic Carbonyl Permethylpentalene Complexes, F.M. Chadwick, A.E. Ashley, R.T. Cooper, L.A. Bennett, J.C. Green and D. O’Hare, Dalton Trans., (2015), 44, 20147-20153.

Double CO2 Activation by 14-electron η8-Permethylpentalene Titanium Dialkyl Complexes, R.T. Cooper, F.M. Chadwick, A.E. Ashley and D. O’Hare, Chemical Communications, (2015), 5, 11856 – 11859.

Synthesis and Characterization of Chiral Group 4 Cyclopentadienyl Complexes and their use in Polymerization of Lactide Monomers, Z.R. Turner, J.-C. Buffet and D. O’Hare, Organometallics, (2014), 33 (14), 3891–3903.