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Wentloog, United Kingdom

Jover J.,University of Bristol | Jover J.,Institute of Chemical Research of Catalonia | Fey N.,University of Bristol | Harvey J.N.,University of Bristol | And 8 more authors.

We have expanded the ligand knowledge base for bidentate P,P- and P,N-donor ligands (LKB-PP, Organometallics 2008, 27, 1372-1383) by 208 ligands and introduced an additional steric descriptor (nHe 8). This expanded knowledge base now captures information on 334 bidentate ligands and has been processed with principal component analysis (PCA) of the descriptors to produce a detailed map of bidentate ligand space, which better captures ligand variation and has been used for the analysis of ligand properties. © 2012 American Chemical Society. Source

Tyler S.N.G.,CatScI Ltd. | Webster R.L.,University of Bath
Chemical Communications

A new amide monomer for step growth polymerisation is reported: the chemistry exploits a bulky malonamide for the synthesis of polyesters and polyamides. No additives are needed and the only by-product, an amine, can be recycled. This journal is © the Partner Organisations 2014. Source

Patel B.,Astrazeneca | Firkin C.R.,Astrazeneca | Snape E.W.,Astrazeneca | Jenkin S.L.,Astrazeneca | And 7 more authors.
Organic Process Research and Development

A brief comparison of the early manufacturing routes to AZD7545 is given. Process development of the preferred long-term manufacturing route is reported in detail, and changes from the initial kilogram-scale route are discussed. Scale-up experience from the pilot-plant manufacture is included in the discussion of each stage. Noteworthy aspects throughout the development of AZD7545 concerned chemical hazards, mechanisms, analysis, and impurities, upon which this case study will focus. © 2012 American Chemical Society. Source

Smith D.A.,University of York | Smith D.A.,CatScI Ltd. | Beweries T.,University of York | Beweries T.,Leibniz Institute for Catalysis at the University of Rostock | And 12 more authors.
Journal of the American Chemical Society

The association constants and enthalpies for the binding of hydrogen bond donors to group 10 transition metal complexes featuring a single fluoride ligand (trans-[Ni(F)(2-C5NF4)(PR3)2], R = Et 1a, Cy 1b, trans-[Pd(F)(4-C5NF4)(PCy3)2] 2, trans-[Pt(F){2-C5NF2H(CF3)}(PCy3)2] 3 and of group 4 difluorides (Cp2MF2, M = Ti 4a, Zr 5a, Hf 6a; Cp2MF2, M = Ti 4b, Zr 5b, Hf 6b) are reported. These measurements allow placement of these fluoride ligands on the scales of organic H-bond acceptor strength. The H-bond acceptor capability β (Hunter scale) for the group 10 metal fluorides is far greater (1a 12.1, 1b 9.7, 2 11.6, 3 11.0) than that for group 4 metal fluorides (4a 5.8, 5a 4.7, 6a 4.7, 4b 6.9, 5b 5.6, 6b 5.4), demonstrating that the group 10 fluorides are comparable to the strongest organic H-bond acceptors, such as Me3NO, whereas group 4 fluorides fall in the same range as N-bases aniline through pyridine. Additionally, the measurement of the binding enthalpy of 4-fluorophenol to 1a in carbon tetrachloride (?23.5 ± 0.3 kJ mol-1) interlocks our study with Laurence's scale of H-bond basicity of organic molecules. The much greater polarity of group 10 metal fluorides than that of the group 4 metal fluorides is consistent with the importance of p?-d? bonding in the latter. The polarity of the group 10 metal fluorides indicates their potential as building blocks for hydrogen-bonded assemblies. The synthesis of trans-[Ni(F){2-C5NF3(NH2)}(PEt3)2], which exhibits an extended chain structure assembled by hydrogen bonds between the amine and metal-fluoride groups, confirms this hypothesis. © 2015 American Chemical Society. Source

Moseley J.D.,CatScI Ltd. | Murray P.M.,CatScI Ltd.
Journal of Chemical Technology and Biotechnology

Transition metal-catalysed reactions are often strongly dependent on ligand and selection, among other factors, which makes discovering the ideal metal/ligand/solvent combination demanding. Furthermore, the effect of ligand and solvent choice is often subtle and unpredictable. This perspective describes how two statistical techniques, design of experiments (DoE) and principal component analysis (PCA), can be combined to guide the decision-making process. The general approach to using these techniques is described, and illustrated with a brief worked example on challenging 'borrowing hydrogen' chemistry. The unique combination of DoE and PCA is a useful decision-making tool to support the selection of ligands and solvents for challenging catalytic reactions. © 2014 Society of Chemical Industry. Source

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