1
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Kundu S, Valiyev I, Mondal D, Rajasekaran VV, Goswami A, Schmittel M. Proton transfer network with luminescence display controls OFF/ON catalysis that generates a high-speed slider-on-deck. RSC Adv 2023; 13:5168-5171. [PMID: 36777932 PMCID: PMC9909384 DOI: 10.1039/d3ra00062a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 01/23/2023] [Indexed: 02/11/2023] Open
Abstract
A three-component network for OFF/ON catalysis was built from a protonated nanoswitch and a luminophore. Its activation by addition of silver(i) triggered the proton-catalyzed formation of a biped and the assembly of a fast slider-on-deck (k 298 = 540 kHz).
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Affiliation(s)
- Sohom Kundu
- Center of Micro and Nanochemistry and (Bio)Technology, Organische Chemie I, Universität Siegen Adolf-Reichwein-Str. 2 D-57068 Siegen Germany +49 2717404356
| | - Isa Valiyev
- Center of Micro and Nanochemistry and (Bio)Technology, Organische Chemie I, Universität Siegen Adolf-Reichwein-Str. 2 D-57068 Siegen Germany +49 2717404356
| | - Debabrata Mondal
- Center of Micro and Nanochemistry and (Bio)Technology, Organische Chemie I, Universität Siegen Adolf-Reichwein-Str. 2 D-57068 Siegen Germany +49 2717404356
| | - Vishnu Verman Rajasekaran
- Center of Micro and Nanochemistry and (Bio)Technology, Organische Chemie I, Universität Siegen Adolf-Reichwein-Str. 2 D-57068 Siegen Germany +49 2717404356
| | - Abir Goswami
- Center of Micro and Nanochemistry and (Bio)Technology, Organische Chemie I, Universität Siegen Adolf-Reichwein-Str. 2 D-57068 Siegen Germany +49 2717404356
| | - Michael Schmittel
- Center of Micro and Nanochemistry and (Bio)Technology, Organische Chemie I, Universität Siegen Adolf-Reichwein-Str. 2 D-57068 Siegen Germany +49 2717404356
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2
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Dekhtyar ML. Brownian Photomotors Based on Organic Compounds: A Review. THEOR EXP CHEM+ 2022. [DOI: 10.1007/s11237-022-09726-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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3
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Jeong Y, Jin S, Palanikumar L, Choi H, Shin E, Go EM, Keum C, Bang S, Kim D, Lee S, Kim M, Kim H, Lee KH, Jana B, Park MH, Kwak SK, Kim C, Ryu JH. Stimuli-Responsive Adaptive Nanotoxin to Directly Penetrate the Cellular Membrane by Molecular Folding and Unfolding. J Am Chem Soc 2022; 144:5503-5516. [PMID: 35235326 DOI: 10.1021/jacs.2c00084] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Biological nanomachines, including proteins and nucleic acids whose function is activated by conformational changes, are involved in every biological process, in which their dynamic and responsive behaviors are controlled by supramolecular recognition. The development of artificial nanomachines that mimic the biological functions for potential application as therapeutics is emerging; however, it is still limited to the lower hierarchical level of the molecular components. In this work, we report a synthetic machinery nanostructure in which actuatable molecular components are integrated into a hierarchical nanomaterial in response to external stimuli to regulate biological functions. Two nanometers core-sized gold nanoparticles are covered with ligand layers as actuatable components, whose folding/unfolding motional response to the cellular environment enables the direct penetration of the nanoparticles across the cellular membrane to disrupt intracellular organelles. Furthermore, the pH-responsive conformational movements of the molecular components can induce the apoptosis of cancer cells. This strategy based on the mechanical motion of molecular components on a hierarchical nanocluster would be useful to design biomimetic nanotoxins.
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Affiliation(s)
- Youngdo Jeong
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Department of HY-KIST Bio-convergence, Hanyang University, Seoul 04763, Republic of Korea
| | - Soyeong Jin
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Department of Chemistry, School of Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - L Palanikumar
- Department of Chemistry, School of Natural Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Huyeon Choi
- Department of Chemistry, School of Natural Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Eunhye Shin
- Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Eun Min Go
- Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Changjoon Keum
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Seunghwan Bang
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Division of Bio-Medical Science & Technology, Biomedical Engineering, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - Dongkap Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Department of Chemistry, School of Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Seungho Lee
- Department of Chemistry, School of Natural Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Minsoo Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Department of Chemistry, School of Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Hojun Kim
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Kwan Hyi Lee
- Biomaterials Research Center, Biomedical Research Division, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Batakrishna Jana
- Department of Chemistry, School of Natural Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Myoung-Hwan Park
- Department of Chemistry & Life Science, Sahmyook University, Seoul 01795, Republic of Korea
| | - Sang Kyu Kwak
- Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Chaekyu Kim
- Fusion Biotechnology, Inc., Ulsan 44919, Republic of Korea
| | - Ja-Hyoung Ryu
- Department of Chemistry, School of Natural Sciences, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
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4
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A boron-transfer mechanism mediating the thermally induced revival of frustrated carbene-borane pairs from their shelf-stable adducts. Commun Chem 2021; 4:137. [PMID: 36697789 PMCID: PMC9814311 DOI: 10.1038/s42004-021-00576-1] [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: 05/19/2021] [Accepted: 09/06/2021] [Indexed: 01/28/2023] Open
Abstract
Chemists have designed strategies that trigger the conformational isomerization of molecules in response to external stimuli, which can be further applied to regulate the complexation between Lewis acids and bases. We have recently developed a system in which frustrated carbene-borane pairs are revived from shelf-stable but external-stimuli-responsive carbene-borane adducts comprised of N-phosphine-oxide-substituted imidazolylidenes (PoxIms) and triarylboranes. Herein, we report the detailed mechanism on this revival process. A thermally induced borane-transfer process from the carbene carbon atom to the N-phosphinoyl oxygen atom initiates the transformation of the carbene-borane adduct. Subsequent conformational isomerization via the rotation of the N-phosphinoyl group in PoxIm moieties eventually leads to the revival of frustrated carbene-borane pairs that can cleave H2. We believe that this work illustrates an essential role of dynamic conformational isomerization in the regulation of the reactivity of external-stimuli-responsive Lewis acid-base adducts that contain multifunctional substituents.
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5
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Abstract
All biological pumps are autonomous catalysts; they maintain the out-of-equilibrium conditions of the cell by harnessing the energy released from their catalytic decomposition of a chemical fuel1-3. A number of artificial molecular pumps have been reported to date4, but they are all either fuelled by light5-10 or require repetitive sequential additions of reagents or varying of an electric potential during each cycle to operate11-16. Here we describe an autonomous chemically fuelled information ratchet17-20 that in the presence of fuel continuously pumps crown ether macrocycles from bulk solution onto a molecular axle without the need for further intervention. The mechanism uses the position of a crown ether on an axle both to promote barrier attachment behind it upon threading and to suppress subsequent barrier removal until the ring has migrated to a catchment region. Tuning the dynamics of both processes20,21 enables the molecular machine22-25 to pump macrocycles continuously from their lowest energy state in bulk solution to a higher energy state on the axle. The ratchet action is experimentally demonstrated by the progressive pumping of up to three macrocycles onto the axle from bulk solution under conditions where barrier formation and removal occur continuously. The out-of-equilibrium [n]rotaxanes (characterized with n up to 4) are maintained for as long as unreacted fuel is present, after which the rings slowly de-thread. The use of catalysis to drive artificial molecular pumps opens up new opportunities, insights and research directions at the interface of catalysis and molecular machinery.
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7
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Qiu Y, Zhang L, Pezzato C, Feng Y, Li W, Nguyen MT, Cheng C, Shen D, Guo QH, Shi Y, Cai K, Alsubaie FM, Astumian RD, Stoddart JF. A Molecular Dual Pump. J Am Chem Soc 2019; 141:17472-17476. [PMID: 31622089 DOI: 10.1021/jacs.9b08927] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Artificial molecular machines (AMMs) built from mechanically interlocked molecules (MIMs) can use energy ratchets to control the unidirectional motion of their component parts. These energy ratchets are operated by the alteration of kinetic barriers and thermodynamic wells, which are, in turn, determined by the switching on and off of noncovalent interactions. Previously, we have developed artificial molecular pumps (AMPs) capable of pumping rings consecutively onto a collecting chain as part of a molecular dumbbell, leading to the formation of rotaxanes. Here, we report a molecular dual pump (MDP) consisting of two individual AMPs linked in a head-to-tail fashion, wherein a single ring is pumped, in a linear manner, on and off a dumbbell involving a [2]rotaxane intermediate by exploiting the redox properties of the two pumps. This MDP, defined by the finely tuned noncovalent interactions and fueled by either chemicals or electricity, utilizes an energy ratchet mechanism to capture a ring and subsequently release it back into solution. The unidirectional motion and the resulting controlled capture and release of the ring were followed by 1D and 2D 1H NMR spectroscopy and supported by control experiments. This molecular dual pump may be considered to be a forerunner of AMMs that are capable of pumping rings across a membrane in a way similar to how bacteriorhodopsin transports protons from one side of a membrane to the other under the influence of light. Such extensive multicomponent AMMs can lead potentially to molecular transporting platforms with positional and directional control of cargo uptake and release when, and only when, instructed.
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Affiliation(s)
- Yunyan Qiu
- 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
| | - Cristian Pezzato
- 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
| | - Weixingyue Li
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Minh T Nguyen
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Chuyang Cheng
- 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
| | - Qing-Hui Guo
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Yi Shi
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Kang Cai
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States
| | - Fehaid M Alsubaie
- Joint Center of Excellence in Integrated Nanosystems , King Abdulaziz City for Science and Technology , Riyadh 11442 , Kingdom of Saudi Arabia
| | - R Dean Astumian
- Department of Physics , University of Maine , 5709 Bennet Hall , Orono , Maine 04469 , United States
| | - J Fraser Stoddart
- Department of Chemistry , Northwestern University , 2145 Sheridan Road , Evanston , Illinois 60208 , United States.,Institute for Molecular Design and Synthesis , Tianjin University , Tianjin 300072 , P. R. China.,School of Chemistry , University of New South Wales , Sydney , NSW 2052 , Australia
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8
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Bakir M, Lawrence MW, Nelson P, Yamin MB. Catalytic C–C cross-coupling and hydrogen evolution by two Pd(II)-complexes of di-2-pyridyl ketone benzoyl hydrazones. J COORD CHEM 2019. [DOI: 10.1080/00958972.2019.1645329] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Mohammed Bakir
- Department of Chemistry, The University of the West Indies-Mona Campus, Jamaica, West Indies
| | - Mark W. Lawrence
- Department of Chemistry, The University of the West Indies-Mona Campus, Jamaica, West Indies
- School of Natural and Applied Sciences, University of Technology, Jamaica, West Indies
| | - Peter Nelson
- Department of Chemistry, The University of the West Indies-Mona Campus, Jamaica, West Indies
| | - M. Bohari Yamin
- Publication Enhancement Unit, Publishing Centre, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia
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9
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Liu D, García-López V, Gunasekera RS, Greer Nilewski L, Alemany LB, Aliyan A, Jin T, Wang G, Tour JM, Pal R. Near-Infrared Light Activates Molecular Nanomachines to Drill into and Kill Cells. ACS NANO 2019; 13:6813-6823. [PMID: 31117378 DOI: 10.1021/acsnano.9b01556] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Using two-photon excitation (2PE), molecular nanomachines (MNMs) are able to drill through cell membranes and kill the cells. This avoids the use of the more damaging ultraviolet light that has been used formerly to induce this nanomechanical cell-killing effect. Since 2PE is inherently confocal, enormous precision can be realized. The MNMs can be targeted to specific cell surfaces through peptide addends. Further, the efficacy was verified through a controlled opening of synthetic bilayer vesicles using the 2PE excitation of MNM that had been trapped within the vesicles.
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Affiliation(s)
| | | | | | | | | | | | - Tao Jin
- Department of Chemistry , North Carolina State University , Raleigh , North Carolina 27695-8204 , United States
| | - Gufeng Wang
- Department of Chemistry , North Carolina State University , Raleigh , North Carolina 27695-8204 , United States
| | | | - Robert Pal
- Department of Chemistry , Durham University , South Road , DH1 3LE Durham , United Kingdom
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10
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Abstract
Bistable [ c2]daisy chain rotaxanes represent a particularly intriguing class of interlocked molecules that can produce internal sliding movements with a net contraction or extension at the single-molecule level. These nanometric motions show some analogies with the sliding motions of actin and myosin filaments in sarcomeres, and this is why [ c2]daisy chain rotaxanes have been also named as “molecular muscles,” as their first synthesis in 2000. In this minireview, the authors discuss the recent history of these molecules, their modular chemical structures, and the various synthetic pathways described in the literature to access them. The authors also detail how their internal motions can be controlled and characterized by a number of chemical and physical tools. The authors finally show that their integration within polymers and materials can give access to synchronized motions and amplifications up to the macroscopic scale. Overall, the numerous examples that have been described in the literature to date demonstrate that this family of molecules has already strongly influenced the entire field of research on artificial molecular machines, and has the potential to be implemented as actuators working at all scales, from nanometric-switchable devices to mechanically active soft matter materials.
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Affiliation(s)
- Antoine Antoine
- SAMS Research Group, Institut Charles Sadron, CNRS, University of Strasbourg BP 84047
| | - Emilie Moulin
- SAMS Research Group, Institut Charles Sadron, CNRS, University of Strasbourg BP 84047
| | - Gad Fuks
- SAMS Research Group, Institut Charles Sadron, CNRS, University of Strasbourg BP 84047
| | - Nicolas Giuseppone
- SAMS Research Group, Institut Charles Sadron, CNRS, University of Strasbourg BP 84047
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11
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Saha S, Biswas PK, Schmittel M. Reversible Interconversion of a Static Metallosupramolecular Cage Assembly into a High-Speed Rotor: Stepless Adjustment of Rotational Exchange by Nucleophile Addition. Inorg Chem 2019; 58:3466-3472. [PMID: 30789716 DOI: 10.1021/acs.inorgchem.8b03567] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The self-assembled cage ROT-1 was prepared from the pyridine-terminated rotator 1, the phenanthroline-appended stator 2, DABCO, and copper(I) ions in a ratio of 1:1:1:4. This four-component assembly is held together by two pyridine→[Cu(phenAr2)]+ as well as two DABCO→zinc porphyrin interactions (phenAr2 = 2,9-diarylphenanthroline) and does not show any motion on the NMR time scale ( k < 0.1 s-1, 298 K). However, it is converted to the fast nanorotor ROT-1 xCD3CN by addition of CD3CN [ x = (v/v)% of acetonitrile in dichloromethane] due to acceleration of both pyridine→copper(I) dissociation steps. Now the rotator is able to visit all four copper(I)-loaded phenanthroline stations of the stator. Depending on the amount of CD3CN, the exchange frequency of the nanorotor varies from 0.7 s-1 (CD3CN:CD2Cl2 = 1:29) to 8000 s-1 (CD3CN:CD2Cl2 = 1:5) at 25 °C. When iodide (I-) is added to the static assembly ROT-1, the rotational speed increases even more drastically ( k = 20 000 s-1), again due to accelerating the rate-determining pyridine→copper(I) dissociation step. In both cases, a sigmoidal relationship is established between exchange frequency and the concentration of added nucleophile (CD3CN or iodide) that suggests the presence of a cooperative effect. Reversible switching between the static assembly and fast rotor was performed several times without any decomposition of the system. In contrast, addition of the common nucleophile PPh3 to ROT-1 does not increase the rotational speed, a finding that is explained on thermodynamic grounds.
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Affiliation(s)
- Suchismita Saha
- Center of Micro- and Nanochemistry and Engineering , Organische Chemie I , Adolf-Reichwein-Str. 2 , D-57068 Siegen , Germany
| | - Pronay Kumar Biswas
- Center of Micro- and Nanochemistry and Engineering , Organische Chemie I , Adolf-Reichwein-Str. 2 , D-57068 Siegen , Germany
| | - Michael Schmittel
- Center of Micro- and Nanochemistry and Engineering , Organische Chemie I , Adolf-Reichwein-Str. 2 , D-57068 Siegen , Germany
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12
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Multi-Component Spirane Assemblies. MACROMOL CHEM PHYS 2018. [DOI: 10.1002/macp.201800218] [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]
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13
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Preston D, Findlay JA, Crowley JD. Recognition Properties and Self‐assembly of Planar [M(2‐pyridyl‐1,2,3‐triazole)2]2+Metallo‐ligands. Chem Asian J 2018; 14:1136-1142. [DOI: 10.1002/asia.201801132] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Dan Preston
- Department of ChemistryUniversity of Otago PO Box 56 Dunedin 9054 New Zealand
| | - James A. Findlay
- Department of ChemistryUniversity of Otago PO Box 56 Dunedin 9054 New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology New Zealand
| | - James D. Crowley
- Department of ChemistryUniversity of Otago PO Box 56 Dunedin 9054 New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology New Zealand
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14
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Findlay JA, Barnsley JE, Gordon KC, Crowley JD. Synthesis and Light-Induced Actuation of Photo-Labile 2-Pyridyl-1,2,3-Triazole Ru(bis-bipyridyl) Appended Ferrocene Rotors. Molecules 2018; 23:E2037. [PMID: 30110981 PMCID: PMC6222349 DOI: 10.3390/molecules23082037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 08/09/2018] [Accepted: 08/09/2018] [Indexed: 11/16/2022] Open
Abstract
To realise useful control over molecular motion in the future an extensive toolbox of both actionable molecules and stimuli-responsive units must be developed. Previously, our laboratory has reported 1,1'-disubstituted ferrocene (Fc) rotor units which assume a contracted/π-stacked conformation until complexation of cationic metal ions causes rotation about the Ferrocene (Fc) molecular 'ball-bearing'. Herein, we explore the potential of using the photochemical ejection of [Ru(2,2'-bipyridyl)₂]2+ units as a stimulus for the rotational contraction of new ferrocene rotor units. Fc rotors with both 'regular' and 'inverse' 2-pyridyl-1,2,3-triazole binding pockets and their corresponding [Ru(2,2'-bipyridyl)₂]2+ complexes were synthesised. The rotors and complexes were characterised using nuclear magnetic resonance (NMR) and ultraviolet (UV)-visible spectroscopies, Electro-Spray Ionisation Mass Spectrometry (ESI⁻MS), and electrochemistry. The 1,1'-disubstituted Fc ligands were shown to π-stack both in solution and solid state. Density Functional Theory (DFT) calculations (CAM-B3LYP/6-31G(d)) support the notion that complexation to [Ru(2,2'-bipyridyl)₂]2+ caused a rotation from the syn- to the anti-conformation. Upon photo-irradiation with UV light (254 nm), photo-ejection of the [Ru(2,2'-bipyridyl)₂(CH₃CN)₂]2+ units in acetonitrile was observed. The re-complexation of the [Ru(2,2'-bipyridyl)₂]2+ units could be achieved using acetone as the reaction solvent. However, the process was exceedingly slowly. Additionally, the Fc ligands slowly decomposed when exposed to UV irradiation meaning that only one extension and contraction cycle could be completed.
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Affiliation(s)
- James A Findlay
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, Otago, New Zealand.
| | - Jonathan E Barnsley
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, Otago, New Zealand.
| | - Keith C Gordon
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, Otago, New Zealand.
| | - James D Crowley
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin 9054, Otago, New Zealand.
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