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Gregory A. Solan

Bio: Gregory A. Solan is an academic researcher from University of Leicester. The author has contributed to research in topics: Catalysis & Methylaluminoxane. The author has an hindex of 35, co-authored 191 publications receiving 6956 citations. Previous affiliations of Gregory A. Solan include Beijing Institute of Clothing Technology & University of Cambridge.


Papers
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Journal ArticleDOI
TL;DR: A new family of olefin polymerization catalysts, derived from iron and cobalt complexes bearing 2,6-bis(imino)pyridyl ligands, was described in this paper.

1,045 citations

Journal ArticleDOI
TL;DR: In this article, the synthesis, characterization, and ethylene polymerization behavior of a series of iron and cobalt halide complexes, LMXn, bearing chelating 2,6-bis(imino)pyridyl ligands L [L = 2.6-(ArNCR1)2C5H3N] is reported.
Abstract: The synthesis, characterization, and ethylene polymerization behavior of a series of iron and cobalt halide complexes, LMXn (M = Fe, X = Cl, n = 2, 3, X = Br, n = 2; M = Co, X = Cl, n = 2), bearing chelating 2,6-bis(imino)pyridyl ligands L [L = 2,6-(ArNCR1)2C5H3N] is reported. X-ray diffraction studies show the geometry at the metal centers to be either distorted square pyramidal or distorted trigonal bipyramidal. Treatment of the complexes LMXn with methylaluminoxane (MAO) leads to highly active ethylene polymerization catalysts converting ethylene to highly linear polyethylene (PE). LFeX2 precatalysts with ketimine ligands (R1 = Me) are approximately an order of magnitude more active than precatalysts with aldimine ligands (R1 = H). Catalyst productivities in the range 3750−20600 g/mmol·h·bar are observed for Fe-based ketimine catalysts, while Co ketimine systems display activities of 450−1740 g/mmol·h·bar. Molecular weights (Mw) of the polymers produced are in the range 14000−611000. Changing reaction ...

970 citations

Journal ArticleDOI
TL;DR: A series of bis(imino)pyridyliron and -cobalt complexes with at least one small ortho substituent, as well as Ar=biphenyl and Ar=naphthyl, has been synthesized as mentioned in this paper.
Abstract: A series of bis(imino)pyridyliron and -cobalt complexes [[2,6-(CR=NAr)2C5H3N]MX2] (R=H, Me; M=Fe, Co; X=Cl, Br) 8-16 containing imino-aryl rings (Ar) with at least one small ortho substituent, as well as Ar=biphenyl and Ar=naphthyl, has been synthesised. Crystallographic analyses of complexes 9 (Ar = 2,3-dimethylphenyl), 13 and 14 (Ar= biphenyl; X= Cl or Br, respectively) reveal a distorted trigonal-bipyramidal geometry in the solid state. These complexes, in combination with methyl aluminoxane (MAO), are active catalysts for the oligomerisation of ethylene, yielding >99% linear alpha-olefin mixtures that follow a Schulz-Flory distribution. Iron ketimine (R = Me) precatalysts give the highest activities and a greater alpha-value than their aldimine (R = H) analogues. Cobalt precatalysts follow a similar trend, though their activities are almost two orders of magnitude lower than those of the corresponding iron catalysts. Ethylene pressure studies on cobalt precatalyst 15 reveal a first-order dependence on ethylene for both the rate of propagation and the rate of chain transfer, and a pressure independence of the alpha value.

335 citations

Journal ArticleDOI
TL;DR: In this paper, the authors focus on recent progress related to structural modifications made to the pre-catalyst, and in particular to the multidentate N imine -ligand manifold, and how these changes impact on thermal stability and activity of the catalyst as well as the microstructural properties of the polyethylene and the distribution of the oligomeric fractions.

198 citations


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01 Jun 2005

3,154 citations

Journal ArticleDOI
TL;DR: While the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice), and I believe that the Handbook can be useful in those laboratories.
Abstract: There is a special reason for reviewing this book at this time: it is the 50th edition of a compendium that is known and used frequently in most chemical and physical laboratories in many parts of the world. Surely, a publication that has been published for 56 years, withstanding the vagaries of science in this century, must have had something to offer. There is another reason: while the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice). I believe that the Handbook can be useful in those laboratories. One of the reasons, among others, is that the various basic items of information it offers may be helpful in new tests, either physical or chemical, which are continuously being published. The basic information may relate

2,493 citations

Journal ArticleDOI
TL;DR: The graph below shows the progression of monoanionic and non-monoanionic ligands through the history of synthesis, as well as some of the properties that have been identified since the discovery of R-Diimine.
Abstract: B. Anionic Ligands 302 IX. Group 9 Catalysts 302 X. Group 10 Catalysts 303 A. Neutral Ligands 303 1. R-Diimine and Related Ligands 303 2. Other Neutral Nitrogen-Based Ligands 304 3. Chelating Phosphorus-Based Ligands 304 B. Monoanionic Ligands 305 1. [PO] Chelates 305 2. [NO] Chelates 306 3. Other Monoanionic Ligands 306 4. Carbon-Based Ligands 306 XI. Group 11 Catalysts 307 XII. Group 12 Catalysts 307 XIII. Group 13 Catalysts 307 XIV. Summary and Outlook 308 XV. Glossary 308 XVI. References 308

2,369 citations