1
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Hum G, Phang SJI, Ong HC, León F, Quek S, Khoo YXJ, Li C, Li Y, Clegg JK, Díaz J, Stuparu MC, García F. Main Group Molecular Switches with Swivel Bifurcated to Trifurcated Hydrogen Bond Mode of Action. J Am Chem Soc 2023. [PMID: 37267593 DOI: 10.1021/jacs.2c12713] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Artificial molecular machines have captured the full attention of the scientific community since Jean-Pierre Sauvage, Fraser Stoddart, and Ben Feringa were awarded the 2016 Nobel Prize in Chemistry. The past and current developments in molecular machinery (rotaxanes, rotors, and switches) primarily rely on organic-based compounds as molecular building blocks for their assembly and future development. In contrast, the main group chemical space has not been traditionally part of the molecular machine domain. The oxidation states and valency ranges within the p-block provide a tremendous wealth of structures with various chemical properties. Such chemical diversity─when implemented in molecular machines─could become a transformative force in the field. Within this context, we have rationally designed a series of NH-bridged acyclic dimeric cyclodiphosphazane species, [(μ-NH){PE(μ-NtBu)2PE(NHtBu)}2] (E = O and S), bis-PV2N2, displaying bimodal bifurcated R21(8) and trifurcated R31(8,8) hydrogen bonding motifs. The reported species reversibly switch their topological arrangement in the presence and absence of anions. Our results underscore these species as versatile building blocks for molecular machines and switches, as well as supramolecular chemistry and crystal engineering based on cyclophosphazane frameworks.
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Affiliation(s)
- Gavin Hum
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Si Jia Isabel Phang
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - How Chee Ong
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Felix León
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Shina Quek
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Yi Xin Joycelyn Khoo
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Chenfei Li
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Yongxin Li
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Jack K Clegg
- School of Chemistry and Molecular Biosciences, The University of Queensland, Cooper Road, St Lucia 4072, Queensland, Australia
| | - Jesús Díaz
- Departamento de Química Orgánica e Inorgánica, Facultad de Veterinaria Extremadura, Avda de la Universidad s/n, Cáceres 10003, Spain
| | - Mihaiela C Stuparu
- School of Chemistry, Chemical Engineering & Biotechnology, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore, Singapore
| | - Felipe García
- Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Julián Claveria 8, Oviedo 33006, Asturias, Spain
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
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2
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Sim Y, Leon F, Hum G, Phang SJI, Ong HC, Ganguly R, Díaz J, Clegg JK, García F. Pre-arranged building block approach for the orthogonal synthesis of an unfolded tetrameric organic-inorganic phosphazane macrocycle. Commun Chem 2022; 5:59. [PMID: 36697579 PMCID: PMC9814789 DOI: 10.1038/s42004-022-00673-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 04/08/2022] [Indexed: 01/28/2023] Open
Abstract
Inorganic macrocycles remain challenging synthetic targets due to the limited number of strategies reported for their syntheses. Among these species, large fully inorganic cyclodiphosphazane macrocycles have been experimentally and theoretically highlighted as promising candidates for supramolecular chemistry. In contrast, their hybrid organic-inorganic counterparts are lagging behind due to the lack of synthetic routes capable of controlling the size and topological arrangement (i.e., folded vs unfolded) of the target macrocycle, rendering the synthesis of differently sized macrocycles a tedious screening process. Herein, we report-as a proof-of-concept-the combination of pre-arranged building blocks and a two-step synthetic route to rationally enable access a large unfolded tetrameric macrocycle, which is not accessible via conventional synthetic strategies. The obtained macrocycle hybrid cyclodiphosphazane macrocycle, cis-[μ-P(μ-NtBu)]2(μ-p-OC6H4C(O)O)]4[μ-P(μ-NtBu)]2 (4), displays an unfolded open-face cavity area of 110.1 Å2. Preliminary theoretical host-guest studies with the dication [MeNC5H4]22+ suggest compound 4 as a viable candidate for the synthesis of hybrid proto-rotaxanes species based on phosphazane building blocks.
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Affiliation(s)
- Ying Sim
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Felix Leon
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Gavin Hum
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Si Jia Isabel Phang
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - How Chee Ong
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Rakesh Ganguly
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
- Shiv Nadar University, NH-91, Tehsil Dadri, Gautam Buddha Nagar, Uttar Pradesh, 201314, India
| | - Jesús Díaz
- Departamento de Química Orgánica e Inorgánica, Facultad de Veterinaria Universidad de Extremadura, Cáceres, Spain.
| | - Jack K Clegg
- School of Chemistry and Molecular Biosciences, Cooper Road, The University of Queensland, St Lucia, 4072, QLD, Australia.
| | - Felipe García
- Division of Chemistry and Biological Chemistry. School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
- Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Julián Claveria 8, Oviedo, 33006, Asturias, Spain.
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3
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Plajer AJ, Bond AD, Wright DS. The Coordination Chemistry of the N-Donor-Substituted Phosphazanes. Chemistry 2021; 27:289-297. [PMID: 32602605 DOI: 10.1002/chem.202002693] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Indexed: 11/12/2022]
Abstract
Phosph(III)azanes, featuring the heterocyclobutane P2 N2 ring, have now been established as building blocks in main-group coordination and supramolecular compounds. Previous studies have largely involved their use as neutral P-donor ligands or as anionic N-donor ligands, derived from deprotonation of amido-phosphazanes [RNHP(μ-NR)]2 . The use of neutral amido-phosphazanes themselves as chelating, H-bond donors in anion receptors has also been an area of recent interest because of the ease by which the proton acidity and anion binding constants can be modulated, by the incorporation of electron-withdrawing exo- and endo-cyclic groups (R) and by the coordination of transition metals to the ring P atoms. We observed recently that the effect of P,N-chelation of metal atoms to the P atoms of cis-[(2-py)NHP(μ-Nt Bu)]2 (2-py=2-pyridyl) not only pre-organises the N-H functionality for optimum H-bonding to anions but also results in a large increase in anion binding constants, well above those for traditional organic receptors like squaramides and ureas. Here, we report a broader investigation of ligand chemistry of [(2-py)NHP(μ-t NBu)]2 (and of the new quinolyl derivative [(8-Qu)NHP(μ-Nt Bu)]2 (8-Qu=8-quinolyl). The additional N-donor functionality of the heterocyclic substituents and its position has a marked effect on the anion and metal coordination chemistry of both species, leading to novel structural behaviour and reactivity compared to unfunctionalized counterparts.
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Affiliation(s)
- Alex J Plajer
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Andrew D Bond
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Dominic S Wright
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
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4
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Shi X, León F, Sim Y, Quek S, Hum G, Khoo YXJ, Ng ZX, Par MY, Ong HC, Singh VK, Ganguly R, Clegg JK, Díaz J, García F. N‐Bridged Acyclic Trimeric Poly‐Cyclodiphosphazanes: Highly Tuneable Cyclodiphosphazane Building Blocks. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xiaoyan Shi
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
- School of Materials and Energy Guangdong University of Technology Guangzhou 510006 Guangdong P. R. China
| | - Felix León
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Ying Sim
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Shina Quek
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Gavin Hum
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Yi Xin Joycelyn Khoo
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Zi Xuan Ng
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Mian Yang Par
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - How Chee Ong
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Varun K. Singh
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
| | - Rakesh Ganguly
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
- Department of Chemistry Shiv Nadar University NH91, Tehsil Dadri Gautam Buddha Nagard 201314 Uttar Pradesh India
| | - Jack K. Clegg
- School of Chemistry and Molecular Biosciences The University of Queensland Cooper Road St Lucia 4072 Queensland Australia
| | - Jesús Díaz
- Departamento de Química Orgánica e Inorgánica Facultad de Veterinaria Universidad de Extremadura Avda de la Universidad s/n 10003 Cáceres Spain
| | - Felipe García
- School of Physical and Mathematical Science Division of Chemistry and Biological Chemistry Nanyang Technological University 21 Nanyang Link 637371 Singapore
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5
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Shi X, León F, Sim Y, Quek S, Hum G, Khoo YXJ, Ng ZX, Par MY, Ong HC, Singh VK, Ganguly R, Clegg JK, Díaz J, García F. N-Bridged Acyclic Trimeric Poly-Cyclodiphosphazanes: Highly Tuneable Cyclodiphosphazane Building Blocks. Angew Chem Int Ed Engl 2020; 59:22100-22108. [PMID: 32696527 DOI: 10.1002/anie.202008214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/16/2020] [Indexed: 01/15/2023]
Abstract
We have synthesized a completely new family of acyclic trimeric cyclodiphosphazane compounds comprising NH, Ni Pr, Nt Bu and NPh bridging groups. In addition, the first NH-bridged acyclic dimeric cyclophosphazane has been produced. The trimeric species display highly tuneable characteristics so that the distance between the terminal N(H)R moieties can be readily modulated by the steric bulk present in the bridging groups (ranging from ≈6 to ≈10 Å). Moreover, these species exhibit pronounced topological changes when a weak non-bonding NH⋅⋅⋅π aryl interaction is introduced. Finally, the NH-bridged chloride binding affinities have been calculated and benchmarked along with the existing experimental data available for monomeric cyclodiphosphazanes. Our results underscore these species as promising hydrogen bond donors for supramolecular host-guest applications.
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Affiliation(s)
- Xiaoyan Shi
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore.,School of Materials and Energy, Guangdong University of Technology, Guangzhou, 510006, Guangdong, P. R. China
| | - Felix León
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Ying Sim
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Shina Quek
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Gavin Hum
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Yi Xin Joycelyn Khoo
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Zi Xuan Ng
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Mian Yang Par
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - How Chee Ong
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Varun K Singh
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
| | - Rakesh Ganguly
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore.,Department of Chemistry, Shiv Nadar University, NH91, Tehsil Dadri, Gautam Buddha Nagard, 201314, Uttar Pradesh, India
| | - Jack K Clegg
- School of Chemistry and Molecular Biosciences, The University of Queensland, Cooper Road, St Lucia, 4072, Queensland, Australia
| | - Jesús Díaz
- Departamento de Química Orgánica e Inorgánica, Facultad de Veterinaria Universidad de Extremadura, Avda de la Universidad s/n, 10003, Cáceres, Spain
| | - Felipe García
- School of Physical and Mathematical Science, Division of Chemistry and Biological Chemistry, Nanyang Technological University, 21, Nanyang Link, 637371, Singapore
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6
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Davis JT, Gale PA, Quesada R. Advances in anion transport and supramolecular medicinal chemistry. Chem Soc Rev 2020; 49:6056-6086. [PMID: 32692794 DOI: 10.1039/c9cs00662a] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Advances in anion transport by synthetic supramolecular systems are discussed in this article. Developments in the design of discrete molecular carriers for anions and supramolecular anion channels are reviewed followed by an overview of the use of these systems in biological systems as putative treatments for diseases such as cystic fibrosis and cancer.
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Affiliation(s)
- Jeffery T Davis
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.
| | - Philip A Gale
- School of Chemistry (F11), The University of Sydney, NSW 2006, Australia.
| | - Roberto Quesada
- Departmento de Química, Universidad de Burgos, 09001 Burgos, Spain.
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7
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Plajer AJ, Lee S, Bond AD, Goodman JM, Wright DS. Charge-assisted phosph(v)azane anion receptors. Dalton Trans 2020; 49:3403-3407. [PMID: 32129399 DOI: 10.1039/d0dt00489h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Coordination of Cu(i) or Pd(ii) to seleno-cyclodiphosph(v)azanes of the type [RNH(Se)P(μ-NtBu)]2 results in positively charged anion receptor units which have increased anion affinity over the neutral seleno-phosph(v)azanes, due to the increase in electrostatic interactions between the receptor and the guest anions. The same effect is produced by replacement of one of the P[double bond, length as m-dash]Se units by a P-Me+ unit.
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Affiliation(s)
- Alex J Plajer
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK.
| | - Sanha Lee
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK.
| | - Andrew D Bond
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK.
| | - Jonathan M Goodman
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK.
| | - Dominic S Wright
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK.
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8
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Plajer AJ, Zhu J, Pröhm P, Rizzuto FJ, Keyser UF, Wright DS. Conformational Control in Main Group Phosphazane Anion Receptors and Transporters. J Am Chem Soc 2020; 142:1029-1037. [PMID: 31877039 DOI: 10.1021/jacs.9b11347] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Anion binding by receptor molecules is a central field of modern chemistry which impacts areas of catalysis as well as biological and materials chemistry. As binding often requires high chemical stability under aerobic and aqueous conditions for practical applications, carbon-based anion receptors have dominated this field, with main group element analogues receiving far less attention. The recent observation that the air- and moisture-stable amino-cyclophosph(V)azanes of the type [RN(E)P(μ-NR)]2 (E = O, S, Se) can exhibit halide binding that is competitive with topologically related organic receptors (such as squaramides and thioureas) has motivated us here to explore how the binding properties of phosphazane receptors can be enhanced further. Coordination of transition metals by the two P,N metal coordination sites of the phosph(III)azane dimer [(2-py)NHP(μ-NtBu)]2 not only activates the receptor for anion binding (by fixing the optimum exo-exo conformation and polarizing the endocyclic N-H substituents) but also stabilizes the P2N2 ring to hydrolysis and oxidation. We show how the binding properties of these receptors can be modulated by the coordinated metal fragments and that they can bind chloride 1 to 2 orders of magnitude stronger than the related squaramides and thioureas. These features can be utilized in anion transport through phospholipid bilayers under aqueous conditions for which transport can be improved by 1 order of magnitude compared to the previous best phosphazane and thiourea transporters. This study demonstrates how careful design of inorganic systems can result in potent supramolecular functionality, beyond that observed for organic counterparts.
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Affiliation(s)
- Alex J Plajer
- Chemistry Department , Cambridge University , Lensfield Road , Cambridge CB2 1EW , U.K
| | - Jinbo Zhu
- Cavendish Laboratory, Department of Physics , Cambridge University , J. J. Thomson Avenue , Cambridge CB3 0HE , U.K
| | - Patrick Pröhm
- Institut für Chemie und Biochemie , Freie Universitaet Berlin Fabeckstr , 34-36 14159 Berlin , Germany
| | - Felix J Rizzuto
- Department of Chemistry , McGill University , 801 Sherbrooke Street W , Montreal , Quebec H3A 0B8 , Canada
| | - Ulrich F Keyser
- Cavendish Laboratory, Department of Physics , Cambridge University , J. J. Thomson Avenue , Cambridge CB3 0HE , U.K
| | - Dominic S Wright
- Chemistry Department , Cambridge University , Lensfield Road , Cambridge CB2 1EW , U.K
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9
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Plajer AJ, Zhu J, Proehm P, Bond AD, Keyser UF, Wright DS. Tailoring the Binding Properties of Phosphazane Anion Receptors and Transporters. J Am Chem Soc 2019; 141:8807-8815. [DOI: 10.1021/jacs.9b00504] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Alex J. Plajer
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Jinbo Zhu
- Cavendish Laboratory, Department of Physics, Cambridge University, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Patrick Proehm
- Institut fuer Chemie und Biochemie, Freie Universitaet Berlin, Fabeckstraße 34-36 14159 Berlin, Germany
| | - Andrew D. Bond
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Ulrich F. Keyser
- Cavendish Laboratory, Department of Physics, Cambridge University, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Dominic S. Wright
- Chemistry Department, Cambridge University, Lensfield Road, Cambridge CB2 1EW, U.K
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10
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Fox F, Neudörfl JM, Goldfuss B. Silanediol versus chlorosilanol: hydrolyses and hydrogen-bonding catalyses with fenchole-based silanes. Beilstein J Org Chem 2019; 15:167-186. [PMID: 30745992 PMCID: PMC6350884 DOI: 10.3762/bjoc.15.17] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 12/22/2018] [Indexed: 01/01/2023] Open
Abstract
Biphenyl-2,2'-bisfenchyloxydichlorosilane (7, BIFOXSiCl2) is synthesized and employed as precursor for the new silanols biphenyl-2,2'-bisfenchyloxychlorosilanol (8, BIFOXSiCl(OH)) and biphenyl-2,2'-bisfenchyloxysilanediol (9, BIFOXSi(OH)2). BIFOXSiCl2 (7) shows a remarkable stability against hydrolysis, yielding silanediol 9 under enforced conditions. A kinetic study for the hydrolysis of dichlorosilane 7 shows a 263 times slower reaction compared to reference bis-(2,4,6-tri-tert-butylphenoxy)dichlorosilane (14), known for its low hydrolytic reactivity. Computational analyses explain the slow hydrolyses of BIFOXSiCl2 (7) to BIFOXSiCl(OH) (8, E a = 32.6 kcal mol-1) and BIFOXSiCl(OH) (8) to BIFOXSi(OH)2 (9, E a = 31.4 kcal mol-1) with high activation barriers, enforced by endo fenchone units. Crystal structure analyses of silanediol 9 with acetone show shorter hydrogen bonds between the Si-OH groups and the oxygen of the bound acetone (OH···O 1.88(3)-2.05(2) Å) than with chlorosilanol 8 (OH···2.16(0) Å). Due to its two hydroxy units, the silanediol 9 shows higher catalytic activity as hydrogen bond donor than chlorosilanol 8, e.g., C-C coupling N-acyl Mannich reaction of silyl ketene acetals 11 with N-acylisoquinolinium ions (up to 85% yield and 12% ee), reaction of 1-chloroisochroman (18) and silyl ketene acetals 11 (up to 85% yield and 5% ee), reaction of chromen-4-one (20) and silyl ketene acetals 11 (up to 98% yield and 4% ee).
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Affiliation(s)
- Falco Fox
- Department für Chemie, Institut für Organische Chemie, Greinstrasse 4, 50939 Köln, Germany
| | - Jörg M Neudörfl
- Department für Chemie, Institut für Organische Chemie, Greinstrasse 6, 50939 Köln, Germany
| | - Bernd Goldfuss
- Department für Chemie, Institut für Organische Chemie, Greinstrasse 4, 50939 Köln, Germany
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11
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Pandey MK, Kunchur HS, Ananthnag GS, Mague JT, Balakrishna MS. Catechol and 1,2,4,5-tetrahydroxybenzene functionalized cyclodiphosphazane ligands: synthesis, structural studies, and transition metal complexes. Dalton Trans 2019; 48:3610-3624. [DOI: 10.1039/c8dt04819c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This paper describes the syntheses of two novel cyclodiphosphazane derivatives and their coordination chemistry with CuI, RuII, RhI, PdII and AuI is also described.
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Affiliation(s)
- Madhusudan K. Pandey
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Harish S. Kunchur
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Guddekoppa S. Ananthnag
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Joel T. Mague
- Department of Chemistry
- Tulane University
- New Orleans
- USA
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12
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Tan D, Ng ZX, Sim Y, Ganguly R, García F. cis-Cyclodiphosph(v/v)azanes as highly stable and robust main group supramolecular building blocks. CrystEngComm 2018. [DOI: 10.1039/c8ce00395e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bench-top stable cis-cyclodiphosph(v/v)azanes are demonstrated to form robust R21(8) bifurcated hydrogen-bonds and PSe⋯Br halogen bonds. This work highlights the potential of cyclodiphosph(v/v)azane building blocks in creating new supramolecular assemblies.
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Affiliation(s)
- Davin Tan
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
- Singapore
| | - Zi Xuan Ng
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
- Singapore
| | - Ying Sim
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
- Singapore
| | - Rakesh Ganguly
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
- Singapore
| | - Felipe García
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
- Singapore
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Sim Y, Tan D, Ganguly R, Li Y, García F. Orthogonality in main group compounds: a direct one-step synthesis of air- and moisture-stable cyclophosphazanes by mechanochemistry. Chem Commun (Camb) 2018. [DOI: 10.1039/c8cc01043a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mechanochemistry has been established to be an environmentally-friendly way of conducting reactions in a solvent-free manner.
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Affiliation(s)
- Ying Sim
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
| | - Davin Tan
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
| | - Rakesh Ganguly
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
| | - Yongxin Li
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
| | - Felipe García
- School of Physical and Mathematical Sciences
- Division of Chemistry and Biological Chemistry
- Nanyang Technological University
- Singapore
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