Post-metallocenes were constructed for olefin polymerization using 1,2,3,4,7,8,9,10-octahydro[1,10]phenanthroline and 1,2,3,4-tetrahydro[1,10]phenanthroline derivatives. A series of zirconium complexes - LZrCl2(NHMe2)2 [L = 2,9-H2-C12H12N2 (4), 2,9-Me2-C12H12N2 (5), 2,9-nBu2-C12H12N2 (6), and 2,9-iPr2-C12H12N2 (7)] - and hafnium complexes - LHfCl2(NHMe2)2 [L = 2,9-H2-C12H12N2 (8), 2,9-Me2-C12H1...

The coordination chemistry of zirconium and hafnium complexes containing the tridentate amine biphenolate ligands [RN(CH2-2-O-3,5-C6H2(tBu)2)2](2-) ([R-ONO](2-); R = tBu (1a), iPr (1b), nPr (1c)) featuring distinct N-alkyl substituents is described. Alcoholysis of Zr(OiPr)4(HOiPr) or Hf(OiPr)4(HOiPr) with H2[1a] in diethyl ether solutions at -35 °C generates the corresponding five-coordinate [1...

A family of zirconium complexes containing bis-, tri- or tetra-BTP ligands (BTP = benzotriazole phenolate) were synthesized and structurally characterized. Treatment of Zr(O(i)Pr)4((i)PrOH) with 2.0 molar equivalents of 2-(2H-benzotriazol-2-yl)-4-(2,4,4-trimethylpentan-2-yl)phenol ((C8)BTP-H) or 2-(2H-benzotriazol-2-yl)-4,6-di-tert-butylphenol ((t-Bu)BTP-H) afforded zirconium alkoxide ([((C8)BT...

The activity of dibenzylzirconium and dibenzylhafnium Salalen complexes in polymerisation of propylene with MAO as a cocatalyst is described. Three Salalen ligand precursors combining a bulky alkyl group (1-adamantyl) on the imine-side phenol and electron withdrawing halo groups of different sizes on the amine-side phenol were explored. All metal complexes were obtained as single diastereomers....

The unusual reactivity of hafnocene complexes in comparison to their titanium and zirconium analogues was dramatically demonstrated in the recent functionalization of coordinated N2 and the coupling of CO2 and N2 to a substituted hydrazine product. The differences in their structure and bonding were also noticed; for example, the s and p ratio of the diene bonding in (s-cis-h-diene) metallocene...

Reaction of [VO(OnPr)3] with the Schiff bases 3,5-(tBu)2-2-OH-C6H2CH(N(x-OR-C6H4)) (R = Me; x = 2, L(1)H; x = 3, L(2)H; x = 4, L(3)H; R = Et (L(4)H), CF3 (L(5)H), Ph (L(6)H)) or 4-methyl-3-(R)-2-(OH)-C6H4C[double bond, length as m-dash]N(2'-(2''-(OR1)C6H4)C6H4) (R = adamantyl, R(1) = Ph (L(7)H) or R = C(Me)2Ph, R(1) = Ph (L(8)H)) afforded the bis(chelate) vanadium(iv) complexes [VO(L(n))2] (n =...

The dinuclear cationic zirconium compound [{Zr( -C5H5)}2( -CH2)( -Cl)( -C5H4-C5H4)][BMe(C6F5)3] 1 reacts in dichloromethane at −78 °C with three equivalents of RNC (R= Bu, 2,6-Me2C6H3) via insertion into the Zr-methylene bond to give the new zirconium cationic species [{Zr( -C5H5)}2(Cl)(CNBu){ -[ -CN(Bu)-CH2-CN(Bu)}( -C5H4-C5H4)][BMe(C6F5)3] 2 and [{Zr( -C5H5)}2(Cl){CN(2,6-Me2C6H3)}[ -{CN(2,6-M...

The increasing availability of the long half-life positron emitter Zr-89 (half life 78.4 h) suggests that it is a strong candidate for cell labelling and hence cell tracking using positron emission tomography. The aim was to produce a range of neutral ZrL4 lipophilic complexes for cell labelling which could be prepared under radiopharmaceutical conditions. This was achieved when the ligand was ...

A series of group 4 amine tris(phenolate) complexes have been prepared and characterised by single crystal X-ray diffraction and multinuclear NMR spectroscopy. It was found that the ligands afforded monomeric titanium complexes and dimeric zirconium structures in the solid-state. The complexes have been tested for the ring-opening polymerisation of rac-lactide under both solution and melt condi...