Novel Multidentate Phosphine and Phosphinite Ligands for Catalytic and Imaging Applications

膦、亚磷酸盐和亚磷酸盐是无机化学中普遍存在的配体。它们被广泛用于螯合大量过渡金属，稳定氧化态和生成催化物质。本项目将研究一系列新的多齿膦和亚膦酸盐配体的合成，这些配体在催化和医学成像方面有潜在的应用。最近，我们的团队开发了一系列多齿膦配合物，这些配合物被发现是有效的催化剂，可以将生物质衍生的酸（如乙酰丙酸）加氢为更高价值的化学品，如1,3-戊二醇和2-甲基四氢呋喃。该项目将建立在这一初步工作的基础上，并研究新的螯合配体对一系列其他生物质衍生底物的催化加氢作用的影响。此外，已知这种多齿螯合配体与99mTc， 188Re， 68Ga和64Cu等金属的相关成像和治疗放射性同位素形成高度稳定的螯合物，因此也将研究这种配体在该领域的应用。目的：-设计和合成一类新的多齿膦和亚磷酸盐配体，使其能够形成稳定的三齿和四齿配合物-系统研究这些配体与一系列过渡金属离子（如Ru， Re和Cu）的配位化学-配合物在催化加氢反应中的应用。工作计划：配体合成：一种使用氯化磷盐生成三齿膦配体的新方法已经在我们的团队中得到了很好的效果。本文将尝试用类似的方法合成新的亚磷酸酯和亚磷酸酯配体。配合物合成：配体与一系列合适的过渡金属前驱盐的反应将被研究。形成的配合物的结构和稳定性将通过核磁共振、x射线衍射、质谱等进行研究，特别是我们将研究Ru形成的催化剂和Re配合物作为研究Tc螯合物的模型。应用：使用我们内部的高压加氢反应器，新生成的催化剂将被筛选用于一系列酸到醇的转化。与伦敦国王学院的同事合作，我们将研究放射性99mTc， 68Ga和188Re的新型螯合物的形成。

Phosphines, phosphinites and phosphites are ubiquitous ligands in inorganic chemistry. They are widely used to chelate a host of transition metals, stabilise oxidation states and generate catalytic species. This project will investigate synthesis of a range of new multidentate phosphine and phosphinite ligands that have potential applications in catalysis and for medical imaging. Recently our group has developed a range of multidentate phosphine complexes that have found to be effective catalysts for the hydrogenation of biomass derived acids, such as levulinic acid, to higher value chemicals like 1,3-pentanediol and 2-methylTHF. This project will build on this initial work and examine the effect new chelating ligands will have on the catalytic hydrogenation of a range of other biomass derived substrates. Additionally, such multidentate chelating ligands are known to form highly stable chelates with relevant imaging and therapy radioistopes of metals such as 99mTc, 188Re, 68Ga and 64Cu, hence applications of such ligands in this field will also be investigated. Objectives:- design and synthesis of a new class of multidentate phosphine and phosphinite ligands that will enable the formation of stable tri and tetradentate complexes- systematic study of the coordination chemistry of these ligands with a range of transition metal ions such as Ru, Re and Cu- application of complexes for catalytic hydrogenation reactions, specifically for the conversion of biomass derived carboxylic acids- application of ligands for the complexation of ligands with relevant metal radioisotopes for imaging applications Work-Plan: Ligand synthesis: A novel approach using phosphonium chloride salts to generate tridentate phosphine ligands has been used to good effect within our group. An analogous route will be attempted for the synthesis of new phosphinite and phosphite ligands. Complex synthesis: reaction of ligands with a range of appropriate transition metal precursor salts will be investigated. The structures and stabilities of the complexes formed will be investigated by NMR, X-ray diffraction, mass spectrometry etc. in particular we will look at Ru for the formation of catalysts and Re complexes as a model for studying Tc chelatesApplications: using our in-house high pressure hydrogenation reactor newly generated catalysts will be screened for a range of acid to alcohol transformations. In collaboration with colleagues at King's College London we will investigate the formation of novel chelates with radioactive 99mTc, 68Ga and 188Re.