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R R N + [(COD)PdCl 2 ] N CH 2 Cl 2 R.T R N N Pd R Cl Cl R NCCH 3 2 AgBF 4 N N Pd R (BF 4 ) 2 NCCH 3 NCCH 3 R' 39, 40, 41 R' 42, 43, 44 45, 46 R' 39, 42, 45: R = i-Pr; R' = H 40, 43, 46: R = i-Pr; R' = Me 41, 44: R = Me; R' = H Figure 7. Syn<strong>thesis</strong> of the pyridinylimine palladium(II) complexes and corresponding counterion complexes. [III] 43 44 Figure 8. Crystal structures of the pyridinylimine palladium(II) complexes 43 and 44. [III] Crystal structures of complexes 43 and 44 are presented in Figure 8. Crystals were obtained by recrystallization from acetone (43) and a mixture of acetone and pentane (1:1). The asymmetric unit of 44 contains two independent, closely similar molecules, whereas only one molecule is present in the asymmetric unit of complex 43. Both palladium compounds have square-planar coordination spheres consisting of two chlorine atoms (Cl1 and Cl2) and two nitrogen atoms of the ligand (N1 and N8). <strong>As</strong> in related pyridinylimine [ 97] and bipyridine [ 98] complexes, in both cases the square structure is slightly deformed as a result of the narrow nitrogen–palladium–nitrogen angle. 28
2.3. Polymerizations Iron(II) and cobalt(II) complexes were studied in the polymerization of ethene and tert-butyl acrylate and palladium(II) complexes in the polymerization of norbornene. 2.3.1. Polymerization of ethene Ethene polymerizations were carried out in a 1 L Büchi glass reactor. In a typical polymerization experiment, the reactor was charged with 200 ml toluene and the system was pressurized with ethene up to the desired concentration; the appropriate amount of the complex and MAO, previously mixed together, were then introduced. Pressure, inside temperature, and the consumption of ethene were recorded as a function of time online with Advantech GENIE® runtime software. The mechanical stirrer was run at 1800 rpm for all experiments to avoid diffusion controlled polymerization reactions. After the preferred polymerization time, the polymerization was stopped by quenching with methanol containing 2% HCl. Polymers were washed with methanol and dried overnight at 70 °C. Molar mass and molar mass distributions were measured by gel permeation chromatography (GPC) relative to polystyrene standards. Of the series of catalyst precursors prepared in this work the most active complex was 26 [(BBzEP)FeCl 2 ], which produced polyethene up to 40860 kg PE/(mol cat. h) (Table 1 entry 6). The catalyst is formed with a ketimine ligand where the ligand bears one benzyl substituent on each phenyl group. Better understanding of the influence of benzyl substituents was sought by preparing iron(II) complexes of the ligands 2,6-bis[(1- phenylimino)ethyl]pyridine (21) and 2,6-bis[(1-(cis)-myrtanylimino)ethyl]pyridine (14) and some corresponding aldimine complexes for comparison. The activity of these complexes very low, however, and no convincing reason was found for the high activity of complex 26. 29
Page 1 and 2: Late Transition Metal Complexes for
Page 3 and 4: Abstract The literature part of the
Page 5 and 6: LIST OF ORGINAL PUBLICATIONS This t
Page 7: Abbreviations 13 C-NMR Carbon nucle
Page 10 and 11: catalyst performance. In 1998 the g
Page 12 and 13: differences. However, the polydispe
Page 14 and 15: + LM + LM + LM P R 2 Al R P + LM CH
Page 16 and 17: catalyzed by metals like tungsten,
Page 18 and 19: N N Pd OH 2 (BF 4 ) 2 + OH 2 -H 2 O
Page 20 and 21: The free radical mechanism involves
Page 22 and 23: 1.2.2. n-Vinyl carbazole and acrylo
Page 24 and 25: 2.1.2. Complexes and solid state st
Page 26 and 27: that carry mixed donor ligands is t
Page 30 and 31: Table 1. Results of ethene polymeri
Page 32 and 33: Palladium(II) complexes with N∩N
Page 34 and 35: polymers increased with monomer con
Page 36 and 37: 3. CONCLUSIONS The discovery of tri
Page 38 and 39: 18. G. J. P. Britovsek, S. Mastroia
Page 40 and 41: 47. (a) F. Peruch, H. Cramail, A. D
Page 42 and 43: 68. (a) Ph. Bayard, R. Jérôme, Ph
Page 44: 95. J. D. Atwood Inorganic and Orga

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