Sullivan, M. R.; Sokkalingam, P.; Nguyen, T.; Donahue, J. P.; Gibb, B. C. Binding of carboxylate and trimethylammonium salts to octa-acid and TEMOA deep-cavity cavitands. Journal of Computer-Aided Molecular Design 2017, 31, 21-28.
Selected Research Publications
Selected Research Publications | 81 Publications
Hillyer, M. B.; Gibb, C.; Sokkalingam, P.; Jordan, J. H.; Ioup, S. E.; Gibb, B. C. Synthesis of Water-Soluble Deep-Cavity Cavitands. Organic Letters 2016, 18, 4048-4051.
Hillyer, M. B.; Gibb, B. C. Molecular Shape and the Hydrophobic Effect. Annual Review of Physical Chemistry 2016, 67, 307-329.
This review focuses on papers published since 2000 on the topic of the properties of solutes in water. More specifically, it evaluates the state of the art of our understanding of the complex relationship between the shape of a hydrophobe and the hydrophobic effect. To highlight this, we present a selection of references covering both empirical and molecular dynamics studies of small (molecular-scale) solutes. These include empirical studies of small molecules, synthetic hosts, crystalline monolayers, and proteins, as well as in silico investigations of entities such as idealized hard and soft spheres, small solutes, hydrophobic plates, artificial concavity, molecular hosts, carbon nanotubes and spheres, and proteins.
Gibb, B. C. From steroids to aqueous supramolecular chemistry: an autobiographical career review. Beilstein Journal of Organic Chemistry 2016, 12, 684-701.
Sokkalingam, P.; Shraberg, J.; Rick, S. W.; Gibb, B. C. Binding Hydrated Anions with Hydrophobic Pockets. Journal of the American Chemical Society 2016, 138, 48-51.
Gibb, C.; . Thermodynamic Profiles of Salt Effects on a Host–Guest System: New Insight into the Hofmeister Effect. The Journal of Physical Chemistry B 2015, 119, 5624-5638.
Sullivan, M. R.; Gibb, B. C. Differentiation of small alkane and alkyl halide constitutional isomers via encapsulation. Org. Biomol. Chem. 2015, 13, 1869-1877.
Previously we have demonstrated that host 1 is capable of hydrocarbon gas separation by selective sequestration of butane from a mixture with propane in the headspace above a solution of the host (C. L. D. Gibb, B. C. Gibb, J. Am. Chem. Soc., 2006, 128, 16498–16499). Expanding on the idea of using this host as a means to affect guest discrimination, we report here on NMR studies of the binding of constitutional isomers of two classes of small molecules: hexanes and chloropentanes. Our results indicate that even with these relatively straightforward classes of molecules, guest binding is complicated. Overall, host 1 displays a preference to bind guests with a X–C(R2)–C(R2)–Me (X = Cl or Me) structure, and more generally, a preference for branched guests rather than highly flexible, unbranched derivatives. The complexity of binding of these isomers is magnified when considering molecular differentiation between pairs of guests. In such cases, different guests demonstrated different propensities to self-sort; some self-sort exclusively, while others show very little propensity to do so. However, whereas the pool of guests reveals some general correlations between binding strength and structure, no obvious relationship between structure and degree of self-sorting was observed.
Carnegie, R. S.; Gribb, C.; Gibb, B. C. Anion Complexation and The Hofmeister Effect. Angewante Chemie International Edition 2014, 53, 11498-11500.
Jordan, J. H.; Gibb, B. C. Molecular containers assembled through the hydrophobic effect. Chem. Soc. Rev. 2015, 44, 547-585.
This review focuses on molecular containers formed by assembly processes driven by the hydrophobic effect, and summarizes the progress made in the field over the last ten years. This small but growing facet of supramolecular chemistry discusses three classes of molecules used by researchers to investigate how self-assembly can be applied to form discrete, mono-dispersed, and structurally well-defined supramolecular entities. The approaches demonstrate the importance of preorganization of arrays of rigid moieties to define a specific form predisposed to bind, fold, or assemble. As the examples demonstrate, studying these systems and their properties is teaching us how to control supramolecular chemistry in water, shedding light on aspects of aqueous solutions chemistry, and illustrating novel applications that harness the unique properties of the hydrophobic effect.
Wanjari, P. P.; Gibb, B. C.; Ashbaugh, H. S. Simulation optimization of spherical non-polar guest recognition by deep-cavity cavitands. J. Chem. Phys. 2013, 139.
Liu, S.; Russell, D. H.; Zinnel, N. F.; Gibb, B. C. Guest Packing Motifs within a Supramolecular Nanocapsule and a Covalent Analogue. Journal of the American Chemical Society 2013, 135, 4314-4324.
Gan, H.; Gibb, B. C. Guest-mediated switching of the assembly state of a water-soluble deep-cavity cavitand. Chem. Commun. 2013, 49, 1395-1397.
Tang, H.; de Oliveira, C. S.; Sonntag, G.; Gibb, C. L. D.; Gibb, B. C.; Bohne, C. Dynamics of a Supramolecular Capsule Assembly with Pyrene. Journal of the American Chemical Society 2012, 134, 5544-5547.
Gan, H.; Gibb, B. C. Guest-controlled self-sorting in assemblies driven by the hydrophobic effect. Chem. Commun. 2012, 48, 1656-1658.
The extent of self-sorting in systems comprised of two different deep-cavity cavitands is investigated. The nature of the guest(s) encapsulated in the resulting assemblies is shown to profoundly influence the extent of self-sorting.
Gibb, B. C. Supramolecular Assembly and Binding in Aqueous Solution: Useful Tips Regarding the Hofmeister and Hydrophobic Effects. Israel Journal of Chemistry 2011, 51, 798-806.
Abstract The self-assembly of structurally discrete entities, and supramolecular chemistry in general, continues to expand into the aqueous realm. To do so, however, requires a firm understanding of the properties of aqueous solution, and how these “change the rules” for binding and assembly relative to organic solvents. In this mini-review we highlight the state-of-the-art understanding of the supramolecular properties of water, and how these influence the design of hosts and self-assembling systems.
Li, Y.; Giles, M. D.; Liu, S.; Laurent, B. A.; Hoskins, J. N.; Cortez, M. A.; Sreerama, S. G.; Gibb, B. C.; Grayson, S. M. A versatile and modular approach to functionalisation of deep-cavity cavitandsvia “click” chemistry. Chem. Commun. 2011, 47, 9036-9038.
The surface modification of deep-cavity cavitands has been demonstrated by using the azide-alkyne “click” coupling to attach dendritic macromolecules or linear polymers onto their periphery. The resulting set of macromolecular cavitands exhibited tuneable solubility yet retained the ability to encapsulate guest molecules.
Gibb, C. L. D.; Gibb, B. C. Anion Binding to Hydrophobic Concavity Is Central to the Salting-in Effects of Hofmeister Chaotropes. Journal of the American Chemical Society 2011, 133, 7344-7347.
Liu, S.; Whisenhunt-Ioup, S. E.; Gibb, C. L. D.; Gibb, B. C. An improved synthesis of 'octa-acid' deep-cavity cavitand. Supramolecular chemistry 2011, 23, 480-485.
An improved synthesis of a water-soluble deep-cavity cavitand (octa-acid, 1) is presented. Previously (Gibb, C. L. D. & Gibb, B. C., J. Am. Chem. Soc., 2004, 126, 11408-11409) we documented access to host 1 in eight (non-linear) steps starting from resorcinol; a synthesis that required four steps involving chromatographic purification. Here we reveal a modified synthesis of host 1. Consisting of seven (non-linear) steps, this new synthesis involves only one chromatographic step, and avoids a minor impurity observed in the original approach. This improved synthesis will therefore be useful for the laboratories that are investigating the properties of these types of host.
Gan, H.; Benjamin, C. J.; Gibb, B. C. Nonmonotonic Assembly of a Deep-Cavity Cavitand. Journal of the American Chemical Society 2011, 133, 4770-4773.
Liu, S.; Gibb, B. C. Solvent denaturation of supramolecular capsules assembled via the hydrophobic effect. Chem. Commun. 2011, 47, 3574-3576.
The organic co-solvent induced denaturation of a series of capsular complexes formed between trioxolane guests and a water-soluble deep-cavity cavitand was examined. The results obtained demonstrate a wide range of denaturation properties, and suggest the important factors governing capsule stability.
Laughrey, Z.; Gibb, B. C. Water-soluble, self-assembling container molecules: an update. Chem. Soc. Rev. 2011, 40, 363-386.
Over the past five years, an important development in the area of self-assembling containers has been the increase in interest in those containers that function in aqueous solution. This progress is a reflection of a similar trend within supramolecular chemistry in general, and is driven in part by the need to address issues and challenges within the biological sciences, as well as a desire to develop new strategies for greener chemistries carried out in water. It is also an opportunity to learn more about fundamental topics such as the hydrophobic effect. In this critical review we discuss progress in aqueous-based self-assembling container molecules since 2005 (177 references).
Liu, S.; Gan, H.; Hermann, A. T.; Rick, S. W.; Gibb, B. C. Kinetic resolution of constitutional isomers controlled by selective protection inside a supramolecular nanocapsule. Nature Chemistry 2010, 2, 847-852.
The concept of self-assembling container molecules as yocto-litre reaction flasks is gaining prominence. However, the idea of using such containers as a means of protection is not well developed. Here, we illustrate this idea in the context of kinetic resolutions. Specifically, we report on the use of a water-soluble, deep-cavity cavitand to bring about kinetic resolutions within pairs of esters that otherwise cannot be resolved because they react at very similar rates. Resolution occurs because the presence of the cavitand leads to a competitive binding equilibrium in which the stronger binder primarily resides inside the host and the weaker binding ester primarily resides in the bulk hydrolytic medium. For the two families of ester examined, the observed kinetic resolutions were highest within the optimally fitting smaller esters.
Grayson, S. M.; Gibb, B. C. Dendronized cavitands: A step towards a synthetic viral capsid?. Soft Matter 2010, 6, 1377-1382.
Dendronized cavitands represent unique macromolecular hosts for encapsulation of biologically relevant guests. They combine the highly specific guest binding exhibited by deep-cavity cavitands, with the modular yet monodisperse macromolecular structure provided by dendrimers. Because these structures retain the ability to assemble into dimeric capsules, they resemble a simplified synthetic analog of viral capsids, displaying a modular, functionalizable outer coating while providing a protective cavity for a range of small-molecule payloads. This article highlights their preparation, their characterization, and their unique potential for probing in vivo drug delivery.
Sundaresan, A. K.; Kaanumalle, L. S.; Gibb, C.; Gibb, B. C.; Ramamurthy, V. Chiral photochemistry within a confined space: diastereoselective photorearrangements of a tropolone and a cyclohexadienone included in a synthetic cavitand. Dalton Transactions 2009, 4003-4011.
The value of a supramolecular assembly to enforce a closer interaction between a chiral auxiliary and a reaction center has been established using photoreactions of tropolone and cyclohexadienone derivatives. Two probe molecules utilized to establish the concept undergo 4 e− electrocyclization and oxa-di-π-methane rearrangement from excited singlet and triplet state, respectively. The chiral auxiliaries investigated here has no/little effect in acetonitrile solution during phototransformations of the probe molecules to yield products with new chiral centers. On the other hand the same ones are able to enforce diastereoselectivities to the extent of ∼30% when the reactions occur within the restricted space of a capsule made up of a synthetic cavitand commonly known as octa acid. Extensive NMR studies have been utilized to characterize the guest–host supramolecular structures. The results presented here should be of value in the overall understanding of chiral induction in photochemical reactions.
Sundaresan, A. K.; Gibb, C. L.; Gibb, B. C.; Ramamurthy, V. Chiral photochemistry in a confined space: torquoselective photoelectrocyclization of pyridones within an achiral hydrophobic capsule. Tetrahedron 2009, 65, 7277-7288.
Chiral induction during the photoelectrocyclization of pyridones included within octa acid (OA) capsule has been established. Chiral induction is brought about by a chiral auxiliary appended to the reactive pyridone moiety. Importantly, the same chiral auxiliary while ineffective in acetonitrile solution is found to be effective within the confined space of OA capsule. The diastereomeric excess of 92% obtained here is comparable only to that in solid state. OA capsule, we believe, provides restriction to the rotational motions of the reactant pyridone and chiral auxiliary and thus places the chiral auxiliary in a selective conformation with respect to the reactive pyridone part. A correlation between the position of the methyl group on the pyridone ring and diastereoselectivity was noted. Structures of the host–guest complexes were examined by 1H NMR and the data were used to obtain preliminary information concerning the mechanism of chiral induction within the confined spaces of OA capsule.