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Studies on mixed complexes of LiCH2CN and lithium amides have shown a large diversity of structures. It is shown that both Li-1 and Li-2 form mixed complexes with LiCH2CN in Et2O and THF solvent, using multinuclear NMR spectroscopy.

Encapsulation complexes are reversibly formed assemblies in which small molecule guests are completely surrounded by large molecule hosts. The assemblies are held together by weak intermolecular forces and are dynamic: they form and dissipate on time scales ranging from milliseconds to days - long enough for many interactions, even reactions, to take place within them. Little information is available on the exchange process, how guests get in and out of these complexes. Here we report that these events can be slow enough for conventional kinetic studies, and reactive intermediates can be detected. Guest exchange has much in common with familiar chemical substitution reactions, but differs in some respects: no covalent bonds are made or broken, the substrate is an assembly rather than a single molecule, and at least four molecules are involved in multiple rate-determining steps.

The novel structures and dynamics of coordination complexes of the chiral lithium amide (S)-2-(1-pyrrolidinylmethyl)pyrrolidide with diamine and TDAM are presented. Dynamic NMR spectroscopy was used to analyzed several moleculardynamic processes including lithium-lithium exchange, diamine ligand exchange and degenerate diamine-amide interconversion. The results showed that the chiral diamine catalyzes intramolecular lithium-lithium exchange when coordinated in its complex with the chiral lithium amide.

A research was conducted to carry out a computational study of a chiral lithium amide. Enthalpies were determined by a semi-empirical calculation method while the chiral amine was obtained using published methods. Results indicated that reference distances from either X-ray or ab initio/PM3 can be utilized to compute for Li-H distances. Findings also showed deviations for distances longer than 4 Angstrom.

The structures of chemical complex molecules capable of self-assembly in organic solvents were studied particularly the capsule that binds smaller molecules of complementary size and shape. These structures occurred as hydrogen bonded dimers in organic solvents. Release of these solvent molecules was involved in the unusual thermodynamic parameters of the encapsulation process. The capsule hastened the biomolecular reaction known as the Diels-Alder reaction since both reactants compatibly occurred in the capsule.

The reaction and solution characteristics of the lithium salt of 2-methoxy-( R -1-phenylethyl)( S -1-phenylethyl)amine were examined. The multinuclear NMR spectra of the salt at temperatures down to -100 degrees C have been obtained in solvents such as diethyl ether (DEE), tetrahydrofuran, dimethoxyethane, toluene and N,N,N',N'-tetramethylethylene diamine. The results showed a dimeric structure with C2 symmetry in DEE with two different lithium resonances in the 6Li NMR.

The NMR spectroscopic analysis has shown that it is possible to perform highly enantioselective asymmetric deprotonation reaction by using i-PrLi or s-BuLi/(+)-sparteine surrogate in THF. The studies have shown that these are the first examples of highly enantioselective asymmetric deprotonation reactions by using organolithium/diamine complexes in THF.

The high reducing power of SmI2/water/amine and YbI2/water/amine in the reduction of unsaturated hydrocarbons having E(sub 1/2) values in the range -1.6 to 3.4 V vs SCE is reported. The results have defined the limiting values of the chemical reducing power of SmI2/H2O/Et3N to -2.8 V and YbI2/H2O/Et3N to -2.3 V vs SCE.

A detailed study highlighting the kinetics of the Sml2/H2O/amine-mediated reduction of 1-chlorodecane is presented. The rate of reaction is first order in amine and 1-chlorodecane, second order in Sml2, and zero order in H2O.

Research has been conducted on SmI (sub)2) /H (sub)2 O/amine mixtures. Results demonstrate that at room temperature these mixtures can reduce alkyl halides with higher efficiency than SmI (sub)2) /HMPA/alcohol mixtures.

The use of a hydroxy softball, an aggregate of 16 hydrogen bonds formed like the seam of a softball, as a catalyst in a Diels-Alder reaction, an interaction between p-benzoquinone and thiopene dioxide derivative in p-xylene-d10 was examined and characterized in several experiments. The findings revealed the important role of molecular capsules such as the hydroxy softball as catalytic reaction chambers in Diels-Alder reactions.

The rates of the dissociation-association process and the mechanism of guest exchange for the 'tennis ball' or the apolar organic solvent held together by a seam of eight hydrogen bonds were investigated. Contrasting rates of reversible encapsulation occur on the human scale and nuclear magnetic resonance time scale after the addition of either methane or ethane. It was also observed that the ring inversion of the seven-membered ring connecting the glycoluril to the aromatic spacer influenced the occurrence of guest exchange in the hydrogen-bonded dimer.

Hogberg's resorcinarenes are useful starting materials for synthetic receptors used in molecular recognition studies, due to their easy synthesis and predictable conformations, making them ideal for cavitands, velcrands and and carcerands. Cavitand complexes featuring unusual kinetic stability in solution are described, with their behaviour related to the effects of hydrogen bonding and conformational dynamics.

The synthesis of a new class of resorcinarene-based cavitands that fold into a deep, open-ended cavity via intramolecular hydrogen bonds revealed eight of the latter along the upper rim of the structure. The amide C=O***H-N interactions connect adjacent rings and are supported by the seven-membered intrannular hydrogen bonds. These self-folding cavitands comprise a new class of molecular containers that are a different species from carcerands and the hydrogen-bonded capsules. The effects of the hydrogen bonds on the behavior of the molecules explain the term 'self.'