OpenUCT :: Browsing by Author "Nassimbeni, Luigi R"

Browsing by Author "Nassimbeni, Luigi R"

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Open Access
Clathration by diol hosts : thermodynamics and structure
(1994) Barbour, Leonard James; Nassimbeni, Luigi R
Inclusion properties of the following seven diol host compounds were investigated: Host 1 9,9'-bis(9,91-dihydroxy-fluorene) Host 2 1, 1'-binaphthyl-2,2'-bis( diphenylhydroxymethyl) Host 3 2,2'-bis(9-hydroxy-9-fluorenyl)biphenyl Host 4 trans-9, 10-dihydroxy-9,10-diphenyl-9, 10-dihydroanthracene Host 5 trans-9, 10-dihydroxy-9,10-di-p-tolyl-9,10-dihydroanthracene Host 6 trans-9, 10-dihydroxy-9, 10-di-p-tert-butylphenyl-9, 10-dihydroanthracene Host 7 trans-9, 10-dihydroxy-9, 10-di-a-naphthyl-9, 10-dihydroanthracene These compounds all possess molecular planes with bulky substituents and opposing hydroxyl moieties as probes for possible coordination to guest molecules by means of hydrogen bonding. Sixteen different inclusion compounds were formed with common organic solvents as the guests. Various characterisation techniques were used and the crystal structures of the inclusion compounds and of the a-phases of Hosts 2 and 5 were elucidated using single crystal X-ray diffraction methods. Thermal decomposition studies using thermogravimetry and differential scanning calorimetry (DSC) were carried out in order to relate the strength of the host-guest interactions to the structures of the inclusion compounds. Owing to practical limitations, the DSC technique is not suitable for the measurement of '1H for the decomposition of an inclusion compound where the guest is relatively volatile. Therefore an apparatus was devised to yield accurate '1H0 values for this process.
Open Access
The crystal and molecular structures of some bioinorganic compounds
(1975) Caira, Mino R; Nassimbeni, Luigi R
In this thesis are presented the results of X-ray structural studies of seven metal-containing crystalline compounds. In some cases, the ligands associated with the metals are themselves biologically active; in other cases, the compound as an entity, rather than any constituent, is of direct or indirect biological significance. Detailed motivations for the individual structural analyses are described in the separate introductions in the body of this work. The compounds studied are generally dissimilar and present different facets of metal-ligand interaction. For this reason, the paragraphs which follow serve to introduce each compound by reviewing the pertinent areas of metal-binding.
Open Access
The crystal and molecular structures of some transition metal-barbiturate complexes
(1974) Rodgers, Allen Lawrence; Nassimbeni, Luigi R
This thesis describes the synthesis and X-ray structural investigation of four complexes of the type M(II)(barb)₂L₂ where M is a transition metal, barb is the anion of a substituted barbituric acid and L is an organic base. These compounds are of importance in the clinical detection and identification of barbiturate drugs and this aspect is discussed in a later section. An infrared study of these compounds is also described. The individual components of the complexes, viz. the transition metals and the barbiturate ligands are in themselves of great biological and physiological significance. Although the human body is but 3% metals, life depends upon these elements far more than this figure suggests. For example, the transition series metals, even though some are present in only trace amounts, generally appear in the active centres of enzymes that catalyze substrates to form aggregate molecules. The barbiturates on the other hand are members of a group of widely used drugs known as hypnotics, many of which are medicinally applied today.
Open Access
Crystal engineering of novel organic-inorganic compounds of N- and O-donor dipyridyl ligands
(2006) Moitsheki, Lesego J; Bourne, Susan A; Nassimbeni, Luigi R
Crystal engineering based upon organic-inorganic compounds has made rapid progress in recent years. These compounds are known to combine the inherent advantages of both organic and inorganic substances. In this thesis, a range of metal compounds were investigated. These include compounds of actinides, lanthanides, transition and main group metals using dipyridyl ligands (4,4'-bipyridine-N,N'-dioxide (bpdo), 1,2-bis(4-pyridyl)ethane (BPE) and 1,2-di(4-pyridyl)ethylene (OPE) Compounds prepared were characterised by x-ray diffractometry. Thermal analysis (thermogravimetry (TG), differential scanning calorimetry (DSC) and hot stage microscopy (HSM)) was used to determine the thermal behaviour of these compounds. Microanalysis was used to confirm elemental composition.
Open Access
The crystal structure of the Adduct [VO(ACA)₂.4-Phenylpyridine]
(1971) Caira, Mino R; Nassimbeni, Luigi R; Li
Open Access
Crystallization of two forms of a cyclodextrin inclusion complex containing a common organic guest
(Royal Society of Chemistry, 2003) Caira, Mino R; De Vries, Elise J C; Nassimbeni, Luigi R
The isolation and structural elucidation by single crystal Xray diffraction of triclinic and monoclinic modifications of an inclusion complex of b-cyclodextrin with the same guest, methylparaben, are reported.
Open Access
Desorption kinetics of a xanthenol-dioxane clathrate
(International Union of Crystallography, 2004) Jacobs, Ayesha; Nassimbeni, Luigi R; Taljaard, Benjamin
The host xanthenol compound forms a 1:1 clathrate with dioxane, namely 9-(1-naphthyl)-9H-xanthen-9-ol–1,4-dioxane, C23H16O2·C4H8O2. The structure of this clathrate is reported, along with a study of the kinetics of desolvation and the determination of an activation energy. The guest molecules are stabilized by Ohost—H⋯Oguest hydrogen bonds [O—H = 0.968 (2) Å, O⋯O = 2.7532 (13) Å and O—H⋯O = 151.9 (4)°].
Open Access
The enclathration of alcohols by cholic acid
(1989) Jones, Elizabeth Louise; Nassimbeni, Luigi R
A series of crystalline Cholic acid inclusion compounds were studied with a view to understanding the role of guest molecules in inducing and stabilizing a particular Cholic acid (host) lattice structure. Alcohols in the series CH₃(CH₂nOH (n= 0 to 3 and 2-propanol) were employed as guest molecules and enclathrated in the host lattice of Cholic acid during crystallization. Single crystal structure analyses were performed by X-ray diffraction. Two types of molecular packing were identified. Cholic acid inclusion compounds with methanol, ethanol and 1-propanol are characterized by a 3-D host and guest molecule network stabilized by hydrogen bonds with symmetry of P2₁2₁2₁ space group. The guest molecules 2- propanol and 1-butanol, by nature of their size, induce a molecular packing with a larger guest cavity than that in the P2₁2₁2₁ space structures. Symmetrically defined by the P6₅22 space group, the crystal lattice is characterized by a helix of Cholic acid molecules generated by the six-fold screw axis through the origin and parallel to the c axis. The lattice is stabilized by an intricate hydrogen bonding scheme. The conformation of Cholic acid (particularly that of the flexible side-chain) in the two types of molecular packing was studied. The size and shape of the guest cavities created by the host lattices were examined. Thermal analyses (Thermogravimetric analysis and Differential Scanning Calorimetry) were performed on these compounds to examine the guest content and the strength of host-guest interactions. ₁₂₃₅
Open Access
Halogen···Halogen interactions in host - guest systems
(2017) Amombo Noa, Francoise Mystere; Nassimbeni, Luigi R; Bourne, Susan A
For a few decades now, halogen bonds which are non-covalent interactions, have gained a lot of interest in the science community due to their applications in diverse research areas. Halogen bonding (XB) is an interaction that occurs between electron deficient halogen compounds and electron donors. This is an established non-covalent interaction in the solid and gaseous phase. In this thesis, the work presented deals with the investigation of halogen bond interactions in host-guest complexes utilising both experimental and theoretical techniques. Two host compounds, tetrakis-4-(bromophenyl)ethylene and its iodo-analogue were synthesised for the studies reported in Chapter 3, 4 and 5. Chapter 3, deals with the classification of halogen···halogen interactions using halogenated methanes as guest solvents. Here, the inclusion complexes can be classified into different types of halogen bonds depending on their geometry. Type I, which are of van der Waals in nature usually have X···X distances greater than the sum of their van der Waals radii. Type IIa and IIb are interactions which are considered to be attractive and their X···X distances are usually shorter than those of type I. The compounds obtained in Chapter 3 were used to study both the kinetics of desolvation and the kinetics of enclathration for the solid host-methyl iodide vapour reactions, to obtain their rate law and determine activation energies. In Chapter 4, the two hosts mentioned above were utilised to form inclusion compounds with a series of halogenated compounds for guest exchange reactions. The structures of the starting inclusion compounds were exposed to the vapours of the second incoming guests to form intermediate complexes and final compounds, which were used to analyse the halogen···halogen interactions in their structures. NMR spectroscopy was performed on selected crystals to monitor the guest exchange experiment and the rate law of each exchange reaction was established. Tetrakis-4-(bromophenyl)ethylene and its iodo-analogue were also used as host compounds in Chapter 5. Here, halogen···halogen interactions are also classified and two novel polymorphs of tetrakis-4-(iodophenyl)ethylene with 3-picoline (3PIC) are reported. Kinetics of enclathration by suspension was conducted on two of the bromohost inclusion compounds (with 3-bromopyridine and 3-picoline) at 25 °C and 35 °C. Competition between hydrogen and halogen bonding was performed in Chapter 6, using three similar but subtly different host compounds with halogenated substituted pyridines as guests. IR spectroscopy and Hirshfeld surface analysis were utilised for further characterisation of these inclusion compounds. The synthesis of halogenated Werner clathrates containing Cl-, Br- and I- in Chapter 7, was conducted with various guests of substituted pyridines. Compounds, which were derived from NiI₂ yielded ionic complexes, forming iodide anions. Iodine was added to these complexes to form tri-iodide anions. The Werner clathrates obtained with the 4-picoline (4PIC) could also be directly synthesised by the exposure of NiCl₂/NiBr₂ to the vapour of 4PIC. Kinetics of enclathration of these two solid-vapour reaction compounds were also analysed. All the structures in this study were elucidated using single crystal X-ray diffraction. Thermal analyses such as thermogravimetry (TG), hot stage microscopy (HSM) and differential scanning calorimetry (DSC) were used for the determination of the thermal behaviour of the new compounds. Variable temperature powder X-ray diffraction was also carried out for the characterisation of the new compounds.
Open Access
Inclusion compounds : structure, reactivity and selectivity
(2002) Su, Hong; Nassimbeni, Luigi R
This thesis is concerned with structure, thermodynamic and kinetic aspects of a variety of inclusion compounds which contain small organic guests. The host compounds studied are alkaline-earth metal salts of O,O’-dibenzoyl-(2R, 3R)-tartraric acid (magnesium, calcium and strontium), 1,1’-bis-(4-hydroxyphenyl)cyclohexane (DHPC) and 2,2’-dihydroxy-1,1’-binaphthyl (BINAP). The alkaline-earth metal salts form coordination complexes with 2-methoxyethanol, water or ethanol and the guests act as a part of the coordination sphere of the metal ions. The diol host DHPC preferably forms layer type inclusion compounds with the isomers of picoline, lutidine and xylidine, as well as a number of selected solvents including 1,4-dioxane, DMSO, morpholine, THF and acetone, preferably in channel type inclusion modes. In the latter two classes of inclusion compounds the inclusion is facilitated by the formation of hydrogen bonds from the host hydroxyl moieties to the guests.
Open Access
Inclusion compounds of multipedal hosts
(1997) Nash, Katherine Lindsay Gifford; Bourne, Susan A; Nassimbeni, Luigi R
The inclusion properties of three multipedal host compounds have been investigated. The host compounds : hexakis(3-hydroxy-3,3-diphenyl-2-propynyl)benzene (host 1), 1,2,3,5,6, 7-hexakis(3-hydroxy-3,3-diphenyl-2-propynyl)naphthalene (host 2), and tetra(3-hydroxy-3,3-diphenyl-2-propynyl)ethylene (host 3), are characterised by a planar electron-rich central region with bulky substituent groups attached to it. Each substituent contains a hydroxyl group capable of hydrogen bonding. These features enable the inclusion of small organic solvent molecules, with suitable functional groups, within the host framework. The crystal structures of selected inclusion compounds and the a-phases of hosts 1 and 3 are presented. The hydrogen bonding patterns and host-guest interactions are analysed. The packing motif of the host compounds and host conformation within each structure is also discussed. The thermal decomposition behaviour of these compounds was investigated using thermogravimetry and differential scanning calorimetry. The kinetics of desolvation for some of the inclusion compounds was determined using isothermal thermogravimetry. Rate laws describing the desolvation mechanisms are ascribed, and the activation energies determined.
Open Access
Inclusion of alkylparabens in cyclodextrins
(2003) De Vries, Elise Janine Christl; Caira, Mino R; Nassimbeni, Luigi R
The aim of this thesis was to prepare crystalline inclusion complexes with cyclodextrins (CDs), as hosts, and drugs, as guests, characterise them using various methods and attempt to elucidate their structures by X-ray diffraction methods to establish the detailed mode of drug inclusion in the solid state. Cyclodextrins and their derivatives have a low polarity central void formed by linked glucose residues of varying numbers. This annular cavity is able to encapsualte low molecular weight molecules and is therefore responsible for the great interest in CDs in host-guest chemistry. In addition, inclusion of drug molecules in cyclodextrins can significantly improve aspects of their performance, such as increased aqueous solubility and dissolution rates which lead to their increasing application in the pharmaceutical industry.
Open Access
Inclusion properties of hydroxy host compounds
(1991) Bourne, Susan Ann; Nassimbeni, Luigi R
Inclusion compounds can be defined as those in which one type of molecule is able to enclose another molecule (usually smaller) within its structure, leaving the bonding systems of both components unchanged. The molecular network and the enclosed species are usually referred to as the "host" and "guest" respectively. The ability of four hydroxyl-containing molecules to form inclusion compounds was studied. Each of these molecules has a tetrahedral carbon or silicon atom bonded to an hydroxyl group and shielded by two or three aromatic moieties. The bulkiness of these molecules prevents them from crystallizing in a close-packed fashion while the hydroxyl groups enable them to participate in hydrogen bonding. The formation and characterisation by single crystal X-ray diffraction methods of two non-porous α-phase compounds and eighteen inclusion compounds have been described. The inclusion compounds were divided into four classes : Class A consisted of compounds of 1, 1,2,2-tetraphenylethane-1,2-diol, Class B consisted of compounds of triphenylmethanol, Class C consisted of compounds of triphenylsilanol and Class D consisted of compounds of tri-1-naphthylsilanol. A number of guest compounds were chosen. Most had at least one atom which could act as an acceptor in a hydrogen bond. Hydrogen bonding (host-host, host-guest or a combination of these) proved to be the greatest stabilizing force in these compounds. The shape and size of the cavities available for guests were analysed by means of volume calculations. The thermal decomposition of the inclusion compounds was studied by Thermogravimetry (TG) and Differential Scanning Calorimetry (DSC), to determine the forces holding the guest within the structure and the changes in the host lattice as the guest was desorbed. X-ray powder diffraction methods were also used to confirm phase changes that occurred with guest loss. In addition, Thermogravimetry was used to determine the activation energy of the guest desorption process. 1, 1,2,2-Tetraphenylethane-1,2-diol was shown to include 3,5-lutidine preferentially from mixtures of 2,6- and 3,5-lutidine, provided that the mole fraction of 3,5-lutidine exceeded 0.30. Triphenylsilanol was selective to ethanol from equimolar mixtures of ethanol and other simple alcohols. Ethanolic solutions of up to 40%(w /w) water also yielded only the 4: 1 triphenylsilanol•ethanol complex. Host-guest interactions were quantified using the method of atom-pair potentials. The position of the guest molecule was varied to allow a minimum potential energy to be calculated. Comparison across a series of related inclusion compounds showed a qualitative correlation between the enthalpy of guest release, ΔH (measured by DSC), and the minimum potential energy of the guest within the crystal structure.
Open Access
Lithium intercalation reactions with transition metal oxides
(1993) Gummow, Rosalind June; Thackeray, Michael; Nassimbeni, Luigi R
An investigation of several lithium transition metal oxide systems has been undertaken with the aim of synthesising an optimised LiM0₂ compound (M = Mn, Co or Co/Ni mixtures) for application as a cathode in rechargeab1e lithium batteries. Attention has been focused on systems which show promise for application as cathodes in rocking-chair cells which do not contain metallic lithium anodes. A novel lithium cobalt oxide, LT-LiCoO₂ (LT for low temperature), has been synthesised at 400°C. This compound has near-cubic symmetry and can be indexed to either a trigonal unit cell (space group R3m) with a=2.830(1)Å and c=l3.875(8) Å, or to a face-centred cubic unit cell (space group Fd3m) with a=8.002(1)A. The near-cubic symmetry is maintained on delithiation. Neutron and X-ray powder diffraction refinement of the LT-LiCoO₂ sample has shown it to be best described as a layered structure (R3m symmetry) with approximately 6% of the cobalt cations in the predominantly lithium layer and vice versa. An acid-leached sample LT-Liₒ₄.4CoO₂ was, however, shown to have a defect spinel structure.
Open Access
Metal complexes of penicillin and cephalosporin antibiotics
(1975) Jackson, Graham Ellis; Nassimbeni, Luigi R; Linder, P W; Fazakerley, G V
The interaction between metal-ions and the penicillin and cephalosporin antibiotics have been studied in an attempt to determine both the site and mechanism of this interaction. The solution conformation of the Cu(II) and Mn(II) complexes were determined using an n.m.r, line broadening, technique. The ligands benzylpenicillin, 6-aminopenicillanic acid, cephalothin, cephalexin, ampicillin and thiaproline were used to study the effect of structural changes in the ligand on the structure of the complex. The stability constants of several metal-ions/penicillin complexes were determined potentiometrically. These were correlated with stability constants determined for several related complexes. Finally the kinetics of the Ni(II) substitution reaction with benzylpenicillin, penicilloic acid, ampicillin and thiaproline was studied.
Open Access
The molecular geometry of d⁸ five-coordination : an analysis of static deformations
(1988) Auf der Heyde, Thomas Paul Edwin; Nassimbeni, Luigi R
The geometries of the ML₅ fragments in 196 five-coordinate metal complexes (M = Ni(II), Pd(II), Pt(II), Rh(I), Ir(I); L = coordinated ligand atom) have been studied using multi-variate statistical techniques. For each molecular fragment the geometry has been precisely described by two sets of twelve non-redundant symmetry coordinates.
Open Access
The optical resolution of albuterol
(1998) Stevens, Anne Theresa; Caira, Mino R; Hunter, Roger; Nassimbeni, Luigi R
The acetonide derivative of (rac)-albuterol has been prepared and used as a substrate in cocrystallisation experiments with several acidic resolving agents~ Successful resolution of the acetonide was achieved with both di-0-benzoyl- and di-0-toluoyltartaric acid, with the (2S,3S)enantiomer of the acid selectively co-crystallising with the desired (R)-albuterol acetonide. High performance liquid chromatography on a chiral stationary phase, and 1H NMR experiments using a chiral shift reagent were used to assess the optical purity of the resolved material. Acid hydrolysis of the resolved acetonide gave rise to the target, (R)-albuterol, which was isolated as an acetate salt. The inferred absolute configuration of the resolved acetonide was assessed by 1H NMR analysis of its (R)-Mosher ester, and confirmed by an X-ray structural determination of its (R)-phenylethylurea derivative. The acetonide derivative of (rac)-albuterol has been prepared and used as a substrate in cocrystallisation experiments with several acidic resolving agents~ Successful resolution of the acetonide was achieved with both di-0-benzoyl- and di-0-toluoyltartaric acid, with the (2S,3S)enantiomer of the acid selectively co-crystallising with the desired (R)-albuterol acetonide. High performance liquid chromatography on a chiral stationary phase, and 1H NMR experiments using a chiral shift reagent were used to assess the optical purity of the resolved material. Acid hydrolysis of the resolved acetonide gave rise to the target, (R)-albuterol, which was isolated as an acetate salt. The inferred absolute configuration of the resolved acetonide was assessed by 1H NMR analysis of its (R)-Mosher ester, and confirmed by an X-ray structural determination of its (R)-phenylethylurea derivative.
Open Access
Physicochemical characterisation of cyclodextrin-drug complexes
(1996) Griffith, Vivienne Jean; Caira, Mino R; Nassimbeni, Luigi R
The cyclodextrins and their derivatives are finding increasing application in the pharmaceutical industry as carrier molecules for many drugs, as complexation can result in improved physical characteristics such as increased aqueous solubility and dissolution rates. The aim of this work was to prepare solid cyclodextrin complexes with selected drugs which have already been shown to interact with cyclodextrins in solution and ultimately to grow crystals of these inclusion complexes of sufficient quality for single crystal X-ray structure determination. The designated drugs included an antibacterial, sulfathiazole; three non-steroidal anti-inflammatory drugs (NSAIDs), (S)-naproxen and the sodium salts of diclofenac and meclofenamic acid; and (L)-menthol, a compound used in many pharmaceutical preparations. The chosen host molecules were ,β-cyclodextrin, γ-cyclodextrin, heptakis(2,6-di-O-methyl)-, β-cyclodextrin (DIMEB) and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TRIMEB). The unit cell parameters of thirteen cyclodextrin-drug complexes and of TRIMEB monohydrate were determined by X-ray photography and the cry tal structures of six of these complexes and of TRIMEB monohydrate were solved. The water content of the complexes was established by thermogravimetric analysis and the host:guest stoichiometries of those complexes whose crystal structures were not solved were determined by UV spectrophotometry or, in one case, by a combination of NMR and thermogravimetric analysis. The complexes were also characterised by differential scanning calorimetry. Hot stage microscopy was a useful method for initial testing for the formation of inclusion complexes of the native cyclodextrins, since their behaviour on heating differs markedly from that of the relevant host alone. The events observed could be correlated with the thermal analyses of the complexes. Complexes which contained alkali metal cations appeared to retain water molecules of crystallisation to higher temperatures, on average, than those which did not. XRD patterns were calculated from the crystal structures which were solved and matched the experimental patterns of the prepared samples well. The calculated patterns serve as the best references for establishing the identity and purity of prepared complexes. Host-guest interactions included hydrogen bonding, van der Waals contacts and hydrophobic interactions. Guest molecules maintained similar conformations on the whole as those observed in other crystal structures containing these particular guests. Conformations of the hosts were akin to those found in known crystal structures, except in TRIMEB monohydrate, where the TRIMEB conformation was distorted to a remarkable extent even in comparison with the distorted conformations observed in its complexes. In addition, one of the methylglucose residues is present in the ¹C₄ inverted chair conformation which has not been observed before in the cyclodextrins or their complexes in the solid state. The invariable occurrence in the TRIMEB host of C(6Gn)-H···0(5Gn-1) hydrogen bonds noted in this study is partly responsible for the uniformity in the conformation of TRIMEB in its complexes. The packing arrangement found in the diclofenac sodium-β-CD complex is unique and is the first example of a β-CD complex crystallising in the hexagonal crystal system. The inclusion by β-CD of meclofenamate sodium (a structural isomer of diclofenac sodium) is similar to that of diclofenac sodium, but the packing arrangement is different and while unique for a complex of unsubstituted β-CD, resembles the packing arrangement found in most of the known TRIMEB complexes.
Open Access
The physio-chemical properties of organic inclusion compounds
(2004) Le Roex, Tanya; Nassimbeni, Luigi R; Caira, Mino R
In this thesis the inclusion properties of the host compounds trans-9,10-dihydroxy-9,10-bis(p-tert-butylphenyl)-9, 10-dihydroanthracene (TBDDDA), 9.9'-(Biphenyl-4,4'diyl) difluoren-9-ol (WEB24) and 1â ´ ,1â ¶,5â ´,5â ¶-tetrahydroxy-2,4,6,8-tetrapentyl-3â ´,3â ¶,7â ´,7â ¶-tetra(p-toluenesulfonyl-oxy)-1,3,5, 7(1,3)-tetrabenzenacyclooctaphane (TTRSC) were investigated. Each of these host compounds is bulky and rigid and in addition contains high-affinity functional groups which can engage in specific host-guest interactions, such as hydrogen bonding.
Open Access
Selectivity in host-guest compounds
(2022) Sykes, Nicole M; Nassimbeni, Luigi R; Bourne Susan A
It isn't easy to separate structurally similar guests by conventional methods such as distillation if the mixture components have similar functional groups and boiling points. This thesis aimed to investigate the relationship between the internal structures of host-guest compounds and the selectivity shown by the host molecule when presented with a guest mixture. Four host compounds were used to prepare 29 new inclusion compounds. Two of these hosts were similar bulky diols and were synthesised by Weber (H1 and H2). The other two, a Nibased Werner-type host (H3) and a brominated host (H4), were synthesised by known methods. In addition, two new structures of the host, H1, alone are reported. Inclusion compounds were prepared by recrystallising the host from liquid guests or exposing the powdered host to guest vapours. The internal structure of the resulting compounds was determined by single crystal X-ray diffraction (XRD), and the secondary interactions between host and guest were carefully studied. The thermal stability of compounds was measured using differential scanning calorimetry, and thermal gravimetry – the latter of which also confirmed the ratio of host to guest within compounds. The preference of a host for one guest over another was determined by exposing the host to mixtures of guests, waiting for crystals to form, and then subjecting these crystals to 1H nuclear magnetic resonance (NMR) spectroscopy or gas chromatography (if guest molecules were indistinguishable by NMR). In some cases, the kinetics of host-guest compound formation and guest exchange was monitored by powder XRD, using an in-house custom-built sample holder. These techniques allowed for the measurement of the relative proportions of guests in the crystals, which was then compared to the ratio of guests from which the host was initially recrystallised. In some cases, it was found that the thermal stability of host-guest compounds correlates with the guest preference of the host. I.e., the guest that formed the most thermally stable host-guest compound is the guest the host prefers. However, it was not always possible to assign structural reasons why this should be the case. In one example, the selectivity of a host was dependent on the temperature of recrystallisation. In another system, the inclusion compound crystallised from a guest mixture had a different structure than when crystallised from either individual guest. In addition, this host's selectivity decreased with time and increasing guest concentration, with concomitant structural changes. While much progress has been made in predicting the structures of single-component crystals, it is still not possible to predict the structures of crystals with multiple components. With the view to predicting the required conditions to grow materials with desired properties, such as being highly selective, more studies on polymorphic inclusion compounds formed under different crystallisation methods are needed.