1
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Speakman NA, Heard AW, Nitschke JR. A Cu I6L 4 Cage Dynamically Reconfigures to Form Suit[4]anes and Selectively Bind Fluorinated Steroids. J Am Chem Soc 2024; 146:10234-10239. [PMID: 38578086 PMCID: PMC11027141 DOI: 10.1021/jacs.4c00257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 03/29/2024] [Accepted: 03/29/2024] [Indexed: 04/06/2024]
Abstract
Simple organic ligands can self-assemble with metal ions to generate metal-organic cages, whose cavities bind guests selectively. This binding may enable new methods of chemical separation or sensing, among other useful functions. Here we report the preparation of a CuI6L4 pseudo-octahedral metal-organic cage, the ligands of which self-assemble from simple organic building blocks. Temperature, solvent, and the presence of different guests governed which structure predominated from a dynamic mixture of cage diastereomers with different arrangements of right- or left-handed metal vertices. Dissolution in dimethyl sulfoxide or the binding of tetrahedral guests led to a chiral tetrahedral T-symmetric framework, whereas low temperatures favored the achiral S4-symmetric diastereomer. Tetrahedral guests with long arms were encapsulated to form mechanically bonded suit[4]anes, with guest arms protruding out through host windows. The cage was also observed to bind fluorinated steroids, an important class of drug molecules, but not non-fluorinated steroids, providing the basis for new separation processes.
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Affiliation(s)
- Natasha
M. A. Speakman
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
| | - Andrew W. Heard
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
- Astex
Pharmaceuticals, 436
Cambridge Science Park, Milton Road, Cambridge CB4 0QA, U.K.
| | - Jonathan R. Nitschke
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
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2
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Martí-Rujas J, Ma S, Famulari A. Experimental X-ray and DFT Structural Analyses of M 12L 8 Poly-[ n]-catenanes Using exo-Tridentate Ligands. Inorg Chem 2022; 61:10863-10871. [PMID: 35771236 PMCID: PMC9937537 DOI: 10.1021/acs.inorgchem.2c01290] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Despite their potential applications in host-guest chemistry, there are only five reported structures of poly-[n]-catenanes self-assembled by elusive M12L8 icosahedral nanocages. This small number of structures of M12L8 poly-[n]-catenanes is because self-assembly of large metal-organic cages (MOCs) with large windows allowing catenation by means of mechanical bonds is very challenging. Structural reports of M12L8 poly-[n]-catenanes are needed to increase our knowledge about the self-assembly and genesis of such materials. Poly-[n]-catenane (1·p-CT) self-assembly of interlocked M12L8 icosahedral cages (M = Zn(II) and L = 2,4,6-tris-(4-pyridyl)benzene (TPB)) including a new aromatic guest (p-chlorotoluene (p-CT)) is reported by single-crystal XRD. Despite the huge internal M12L8 voids (> 2500 Å3), p-CT is ordered, allowing a clear visualization of the relative host-guest positions. DFT calculations have been used to compute the electrostatic potential of the TPB ligand, and various aromatic guests (i.e., o-dichlorobenzene (o-DCB), p-chloroanisole (p-CA), and nitrobenzene (NBz)) included (ordered) within the M12L8 cages were determined by single-crystal XRD. The computed maps of electrostatic potential (MEPs) allow for the rationalization of the guest's inclusion seen in the 3D X-ray structures. Although more crystallographic X-ray structures and DFT analysis are needed to gain insights of guest inclusion in the large voids of M12L8 poly-[n]-catenanes, the reported combined experimental/DFT structural analyses approach can be exploited to use isostructural M12L8 poly-[n]-catenanes as hosts for molecular separation and could find applications in the crystalline sponge method developed by Fujita and co-workers. We also demonstrate, exploiting the instant synthesis method, in solution (i.e., o-DCB), and in the solid-state by neat grinding (i.e., without solvent), that the isostructural M12L8 poly-[n]-catenane self-assembled with 2,4,6-tris-(4-pyridyl)pyridine (TPP) ligand and ZnX2 (where X = Cl, Br, and I) can be kinetically synthesized as crystalline (yields ≈ 60%) and amorphous phases (yields ≈ 70%) in short time and large quantities. Despite the change in the aromatic nature at the center of the rigid exo-tridentate pyridine-based ligand (TPP vs TPB), the kinetic control gives the poly-[n]-catenanes selectively. The dynamic behavior of the TPP amorphous phases upon the uptake of aromatic guest molecules can be used in molecular separation applications like benzene derivatives.
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Affiliation(s)
- Javier Martí-Rujas
- Dipartimento
di Chimica Materiali e Ingegneria Chimica “Giulio Natta”, Politecnico di Milano, Via Luigi Mancinelli 7, Milan 20131, Italy,Center
for Nano Science and Technology@Polimi, Istituto Italiano di Tecnologia, Via Pascoli 70/3, Milan 20133, Italy,
| | - Sijie Ma
- Dipartimento
di Chimica Materiali e Ingegneria Chimica “Giulio Natta”, Politecnico di Milano, Via Luigi Mancinelli 7, Milan 20131, Italy
| | - Antonino Famulari
- Dipartimento
di Chimica Materiali e Ingegneria Chimica “Giulio Natta”, Politecnico di Milano, Via Luigi Mancinelli 7, Milan 20131, Italy,INSTM
Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia
dei Materiali, Florence 50121, Italy,
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3
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Abstract
SignificanceDuring the past decades, the development of efficient methodologies for the creation of mechanically interlocked molecules (MIMs), such as catenanes and rotaxanes, has not only laid the foundation for the design and syntheses of artificial molecular machines (AMMs) but also opened up new research opportunities in multiple disciplines, ranging from contemporary chemistry to materials science. In this study, we describe a suitane-based strategy for the construction of three-dimensional (3D) catenanes, a subset of MIMs that are far from easy to make. Together with synthetic methodologies based on the metal coordination and dynamic covalent chemistry, this approach brings us one step closer to realizing routine syntheses of 3D catenanes.
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4
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Xie H, Gunawardana VWL, Finnegan TJ, Xie W, Badjić JD. Picking on Carbonate: Kinetic Selectivity in the Encapsulation of Anions. Angew Chem Int Ed Engl 2022; 61:e202116518. [PMID: 35038355 DOI: 10.1002/anie.202116518] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Indexed: 12/21/2022]
Abstract
Supramolecular hosts bind to inorganic anions at a fast rate and select them in proportion with thermodynamic stability of the corresponding [anion⊂host] complexes, forming in a reversible manner. In this study, we describe the action of hexapodal capsule 1 and its remarkable ability to select anions based on a large span of rates by which they enter this host. The thermodynamic affinity of 1 toward eighteen anions extends over eight orders of magnitude (0<Ka <108 M-1 ; 1 H NMR spectroscopy). The capsule would retain CO3 2- (Ka =107 M-1 ) for hours in the presence of eleven competing anions, including stronger binding SO4 2- , HAsO4 2- and HPO4 2- (Ka =107 -108 M-1 ). The observed selection resulted from 1 possessing narrow apertures (ca. 3×6 Å) comparable in size to anions (d=3.5-7.1 Å) slowing down the encapsulation to last from seconds to days. The unorthodox mode of action of 1 sets the stage for creating hosts that pick anions by their ability to access the host.
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Affiliation(s)
- Han Xie
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
| | | | - Tyler J Finnegan
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
| | - William Xie
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
| | - Jovica D Badjić
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
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5
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Badjic JD, Xie H, Gunawardana VWL, Finnegan TJ, Xie W, Badjić JD. Picking on Carbonate: Kinetic Selectivity in the Encapsulation of Anions. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jovica D Badjic
- Ohio State University Department of Chemistry 100 W. 18th Avenue 43210 Columbus UNITED STATES
| | - Han Xie
- The Ohio State University Chemistry and Biochemistry UNITED STATES
| | | | | | - William Xie
- The Ohio State University Chemistry and Biochemistry UNITED STATES
| | - Jovica D. Badjić
- The Ohio State University Chemistry and Biochemistry UNITED STATES
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6
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Ibáñez S, Vicent C, Peris E. Clippane: A Mechanically Interlocked Molecule (MIM) Based on Molecular Tweezers. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202112513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Susana Ibáñez
- Institute of Advanced Materials (INAM) Universitat Jaume I Av. Vicente Sos Baynat s/n 12071 Castellón Spain
| | - Cristian Vicent
- Servei Central d'Instrumentació Científica (SCIC) Universitat, Jaume I Avda. Sos Baynat s/n 12006 Castellón Spain
| | - Eduardo Peris
- Institute of Advanced Materials (INAM) Universitat Jaume I Av. Vicente Sos Baynat s/n 12071 Castellón Spain
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7
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Ibáñez S, Vicent C, Peris E. Clippane: A Mechanically Interlocked Molecule (MIM) Based on Molecular Tweezers. Angew Chem Int Ed Engl 2021; 61:e202112513. [PMID: 34633757 DOI: 10.1002/anie.202112513] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Indexed: 12/15/2022]
Abstract
In this study we report the preparation of a new mechanically interlocked molecule formed by the self-aggregation of two metallotweezers composed by two pyrene-imidazolylidene gold(I) arms and a pyridine-centered pentacyclic bis-alkynyl linker. The mechanically interlocked nature of this molecule arises from the presence of the bulky tert-butyl groups attached to the sides of the pyrene moieties of the arms of the tweezer, which act as stoppers avoiding the dissociation of the self-aggregated metallotweezer dimer once it is formed. By combining experimental techniques, we were able to confirm the mechanically interlocked nature of this molecule in solution, in the gas phase and in the solid state. The behavior of the tert-butyl substituted tweezer differs greatly form that shown by the tweezer lacking of these bulky groups, whose dimeric structure is in equilibrium with the monomeric structure, therefore not showing any mechanical coercion that avoids the disassembly of the self-aggregated structure.
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Affiliation(s)
- Susana Ibáñez
- Institute of Advanced Materials (INAM), Universitat Jaume I, Av. Vicente Sos Baynat s/n, 12071, Castellón, Spain
| | - Cristian Vicent
- Servei Central d'Instrumentació Científica (SCIC), Universitat, Jaume I, Avda. Sos Baynat s/n, 12006, Castellón, Spain
| | - Eduardo Peris
- Institute of Advanced Materials (INAM), Universitat Jaume I, Av. Vicente Sos Baynat s/n, 12071, Castellón, Spain
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8
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Liu W, Tan Y, Jones LO, Song B, Guo QH, Zhang L, Qiu Y, Feng Y, Chen XY, Schatz GC, Stoddart JF. PCage: Fluorescent Molecular Temples for Binding Sugars in Water. J Am Chem Soc 2021; 143:15688-15700. [PMID: 34505510 DOI: 10.1021/jacs.1c06333] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The development of synthetic receptors that recognize carbohydrates in water with high selectivity and specificity is challenging on account of their structural complexity and strong hydrophilicity. Here, we report on the design and synthesis of two pyrene-based, temple-shaped receptors for the recognition of a range of common sugars in water. These receptors rely on the use of two parallel pyrene panels, which serve as roofs and floors, capable of forming multiple [C-H···π] interactions with the axially oriented C-H bonds on glycopyranosyl rings in the carbohydrate-based substrates. In addition, eight polarized pyridinium C-H bonds, projecting from the roofs and floors of the temple receptors toward the binding cavities, form [C-H···O] hydrogen bonds, with the equatorially oriented OH groups on the sugars located inside the hydrophobic cavities. Four para-xylylene pillars play a crucial role in controlling the distance between the roof and floor. These temple receptors are highly selective for the binding of glucose and its derivatives. Furthermore, they show enhanced fluorescence upon binding with glucose in water, a property which is useful for glucose-sensing in aqueous solution.
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Affiliation(s)
- Wenqi Liu
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - Yu Tan
- School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Leighton O Jones
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - Bo Song
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - Qing-Hui Guo
- Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310027, China.,ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China
| | - Long Zhang
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - Yunyan Qiu
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - Yuanning Feng
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - Xiao-Yang Chen
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - George C Schatz
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States
| | - J Fraser Stoddart
- Department of Chemistry, 2145 Sheridan Road, Northwestern University, Evanston, Illinois 60208, United States.,School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia.,Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou 310027, China.,ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311215, China
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9
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Valencia-Loza SDJ, López-Olvera A, Martínez-Ahumada E, Martínez-Otero D, Ibarra IA, Jancik V, Percástegui EG. SO 2 Capture and Oxidation in a Pd6L8 Metal-Organic Cage. ACS APPLIED MATERIALS & INTERFACES 2021; 13:18658-18665. [PMID: 33871959 DOI: 10.1021/acsami.1c00408] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The facile and green preparation of novel materials that capture sulfur dioxide (SO2) with significant uptake at room temperature remains challenging, but it is crucial for public health and the environment. Herein, we explored for the first time the SO2 adsorption within microporous metal-organic cages using the palladium(II)-based [Pd6L8](NO3)36 tetragonal prism 1, assembled in water under mild conditions. Notably and despite the low BET surface area of 1 (111 m2 g-1), sulfur dioxide was found to be irreversibly and strongly adsorbed within the activated cage at 298 K (up to 6.07 mmol g-1). The measured values for the molar enthalpy of adsorption (ΔHads) coupled to the FTIR analyses imply a chemisorption process that involves the direct interaction of SO2 with Pd(II) sites and the subsequent oxidation of this toxic chemical by the action of the nitrate anions in 1. To the best of our knowledge, this is the first reported metal-organic cage that proves useful for SO2 adsorption. Metallosupramolecular adsorbents such as 1 could enable new detection applications and suggest that the integration of soft metal ions and self-assembly of molecular cages are a potential means for the easy tuning of SO2 adsorption capabilities and behavior.
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Affiliation(s)
- Sergio de Jesús Valencia-Loza
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Ciudad de México 04510 México
- Centro Conjunto de Investigación en Química Sustentable, UAEM-UNAM. Carretera Toluca-Atlacomulco Km 14.5, Toluca, Estado de México 50200, México
| | - Alfredo López-Olvera
- Laboratorio de Fisicoquímica y Reactividad de Superficies (LaFReS), Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, CU, Del Coyoacán, México D.F. 04510, México
| | - Eva Martínez-Ahumada
- Laboratorio de Fisicoquímica y Reactividad de Superficies (LaFReS), Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, CU, Del Coyoacán, México D.F. 04510, México
| | - Diego Martínez-Otero
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Ciudad de México 04510 México
- Centro Conjunto de Investigación en Química Sustentable, UAEM-UNAM. Carretera Toluca-Atlacomulco Km 14.5, Toluca, Estado de México 50200, México
| | - Ilich A Ibarra
- Laboratorio de Fisicoquímica y Reactividad de Superficies (LaFReS), Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, CU, Del Coyoacán, México D.F. 04510, México
| | - Vojtech Jancik
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Ciudad de México 04510 México
- Centro Conjunto de Investigación en Química Sustentable, UAEM-UNAM. Carretera Toluca-Atlacomulco Km 14.5, Toluca, Estado de México 50200, México
| | - Edmundo G Percástegui
- Universidad Nacional Autónoma de México, Instituto de Química, Ciudad Universitaria, Ciudad de México 04510 México
- Centro Conjunto de Investigación en Química Sustentable, UAEM-UNAM. Carretera Toluca-Atlacomulco Km 14.5, Toluca, Estado de México 50200, México
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10
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Xu H, Lin MD, Yuan J, Zhou B, Mu Y, Huo Y, Zhu K. Fluorescence emission enhancement of a T-shaped benzimidazole with a mechanically-interlocked 'suit'. Chem Commun (Camb) 2021; 57:3239-3242. [PMID: 33646217 DOI: 10.1039/d0cc07471c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A fluorescent T-shaped benzimidazole was successfully designed and interlocked in a bicyclic macrocycle to form a suit[1]ane through supramolecular templated-synthesis. Compared with the bare fluorophore, suit[1]ane requires nearly two times the concentration to initialize the aggregation-caused quenching effect in solution. Furthermore, an 8-fold higher solid-state fluorescence quantum yield (21.7%) is also achieved. By taking advantage of mechanical bonding and molecular packing, such fluorescence emission enhancement through formation of a suitane opens the way to new complex fluorescent materials.
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Affiliation(s)
- Houyang Xu
- School of Chemistry, Sun Yat-sen University, Guangzhou, 510275, China.
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11
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12
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Chen XY, Shen D, Cai K, Jiao Y, Wu H, Song B, Zhang L, Tan Y, Wang Y, Feng Y, Stern CL, Stoddart JF. Suit[3]ane. J Am Chem Soc 2020; 142:20152-20160. [PMID: 33180476 DOI: 10.1021/jacs.0c09896] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Suitanes are a class of mechanically interlocked molecules (MIMs) that consist of two components: a body with limbs protruding outward and a suit that fits appropriately around it, so that there is no easy way for the suit to be removed from the body. Herein, we report the synthesis and characterization of a suit[3]ane, which contains a benzotrithiophene derivative (THBTT) with three protruding hexyl chains as the body and a 3-fold symmetric, extended pyridinium-based cage, namely, HexaCage6+, as the suit. Central to its realization is effective templation, provided by THBTT during cage formation, an observation that has been supported by the strong binding constant between benzotrithiophene (BTT) and the empty cage. The solid-state structure of the suit[3]ane reveals that the body is confined within the suit's cavity with its alkyl chains protruding outward through the orifices in the cage. Notably, such a seemingly unstable molecule, having three flexible alkyl chains as its only protruding limbs, does not dissociate after prolonged heating in CD3CN at 100 °C under pressure for 7 days. No evidence for guest exchange with the host was observed at this temperature in a 2:1 mixture of THBTT and HexaCage6+ in CD3CN. The results indicate that flexible protruding limbs are sufficient for a suit[3]ane to remain mechanically stable even at high temperatures in solution.
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Affiliation(s)
- Xiao-Yang Chen
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Dengke Shen
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Kang Cai
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Yang Jiao
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Huang Wu
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Bo Song
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Long Zhang
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Yu Tan
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Yu Wang
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Yuanning Feng
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Charlotte L Stern
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - J Fraser Stoddart
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.,School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
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