Main Group Hydrogen-Bond Donors and Pyridyl Ligands for Supramolecular and Coordination Chemistry
type: CreativeWork
description: The thesis involves the investigation of two main areas in which new ligands based on main group frameworks are developed. In the first part of this thesis we explore the host-guest chemistry of a range of non-carbon frameworks based on P-N bonds. In the first chapter we develop strategies for enhancing the anion binding properties of phosphazanes of the type [(RNH)(E)P(µ-NtBu)]2 (E = O, S, Se) which are bench stable, H-bond receptors that can be regarded as inorganic analogues of squaramides (a key class of organic anion receptor). We find that there are distinct advantages of these inorganic receptors over organic counterparts such as the ease by which their functionality and electronic character can be altered (by means of the R-groups and chalcogenide present). Selenium substitution at the phosphine-centres, the presence of electron withdrawing R-groups and metal coordination to the soft donor centres can be used to modulate and enhance anion binding. The water stability and superior anion binding properties of the selenophosph(V)azanes gives them applications as synthetic anion transporters through phospholipid bilayers. Next, we establish synthetic methodologies for the rational design of bimetallic phosphazane coordination complexes of the type [LnM(PyridylNH)P(µ-NtBu)]2 (M = transition metal, L = supporting ligand). By optimisation of the NH bond polarity we achieve halide binding approximately one order of magnitude stronger than for organic analogues. We find that metal coordination renders these complexes robust enough to function as synthetic anion transporters through phospholipid bilayers and reveal how metal coordination affects the transport activity. We also investigate the general coordination chemistry of the parent ligand and the effect of quinolyl substitution. Finally, we investigate the host-guest chemistry of pentameric phosphazane macrocycle {[NHP(µ-NtBu)]2}5. The polar coordination site of this system promotes new modes of guest encapsulati…
abstract: The thesis involves the investigation of two main areas in which new ligands based on main group frameworks are developed. In the first part of this thesis we explore the host-guest chemistry of a range of non-carbon frameworks based on P-N bonds. In the first chapter we develop strategies for enhancing the anion binding properties of phosphazanes of the type [(RNH)(E)P(µ-NtBu)]2 (E = O, S, Se) which are bench stable, H-bond receptors that can be regarded as inorganic analogues of squaramides (a key class of organic anion receptor). We find that there are distinct advantages of these inorganic receptors over organic counterparts such as the ease by which their functionality and electronic character can be altered (by means of the R-groups and chalcogenide present). Selenium substitution at the phosphine-centres, the presence of electron withdrawing R-groups and metal coordination to the soft donor centres can be used to modulate and enhance anion binding. The water stability and superior anion binding properties of the selenophosph(V)azanes gives them applications as synthetic anion transporters through phospholipid bilayers. Next, we establish synthetic methodologies for the rational design of bimetallic phosphazane coordination complexes of the type [LnM(PyridylNH)P(µ-NtBu)]2 (M = transition metal, L = supporting ligand). By optimisation of the NH bond polarity we achieve halide binding approximately one order of magnitude stronger than for organic analogues. We find that metal coordination renders these complexes robust enough to function as synthetic anion transporters through phospholipid bilayers and reveal how metal coordination affects the transport activity. We also investigate the general coordination chemistry of the parent ligand and the effect of quinolyl substitution. Finally, we investigate the host-guest chemistry of pentameric phosphazane macrocycle {[NHP(µ-NtBu)]2}5. The polar coordination site of this system promotes new modes of guest encapsulati…
author: Plajer, Alex Johannes
language: en
keywords: Main group chemistry, Coordination chemistry, Supramolecular Chemistry
license: https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/e5e9b367-670a-4502-bdef-f36775eca3fe/download
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2020-02-10
date modified: 2026-07-22T22:24:20Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.48118