| 1. |
- Canton, Martina, et al.
(författare)
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Improving Fatigue Resistance of Dihydropyrene by Encapsulation within a Coordination Cage
- 2020
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 142:34, s. 14557-14565
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Tidskriftsartikel (refereegranskat)abstract
- Photochromic molecules undergo reversible isomerization upon irradiation with light at different wavelengths, a process that can alter their physical and chemical properties. For instance, dihydropyrene (DHP) is a deep-colored compound that isomerizes to light-brown cyclophanediene (CPD) upon irradiation with visible light. CPD can then isomerize back to DHP upon irradiation with UV light or thermally in the dark. Conversion between DHP and CPD is thought to proceed via a biradical intermediate; bimolecular events involving this unstable intermediate thus result in rapid decomposition and poor cycling performance. Here, we show that the reversible isomerization of DHP can be stabilized upon confinement within a (PdIIL4)-L-6 coordination cage. By protecting this reactive intermediate using the cage, each isomerization reaction proceeds to higher yield, which significantly decreases the fatigue experienced by the system upon repeated photocycling. Although molecular confinement is known to help stabilize reactive species, this effect is not typically employed to protect reactive intermediates and thus improve reaction yields. We envisage that performing reactions under confinement will not only improve the cyclic performance of photochromic molecules, but may also increase the amount of product obtainable from traditionally low-yielding organic reactions.
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| 2. |
- Grommet, Angela Beth, 1991, et al.
(författare)
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Chemical Reactivity Under Nanoconfinement
- 2020
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Ingår i: Nature Nanotechnology. - : Springer Science and Business Media LLC. - 1748-3387 .- 1748-3395. ; 15:4, s. 256-271
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Forskningsöversikt (refereegranskat)
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| 3. |
- Grommet, Angela Beth, 1991, et al.
(författare)
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Molecular Photoswitching in Confined Spaces
- 2020
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Ingår i: Accounts of Chemical Research. - : American Chemical Society (ACS). - 0001-4842 .- 1520-4898. ; 53:11, s. 2600-2610
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Forskningsöversikt (refereegranskat)
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| 4. |
- Kuntrapakam, Hema, et al.
(författare)
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Guest Encapsulation Alters the Thermodynamic Landscape of a Coordination Host
- 2023
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Ingår i: Journal of the American Chemical Society. - 1520-5126 .- 0002-7863. ; 145:45, s. 24755-24764
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Tidskriftsartikel (refereegranskat)abstract
- The architecture of self-assembled host molecules can profoundly affect the properties of the encapsulated guests. For example, a rigid cage with small windows can efficiently protect its contents from the environment; in contrast, tube-shaped, flexible hosts with large openings and an easily accessible cavity are ideally suited for catalysis. Here, we report a “Janus” nature of a Pd6L4 coordination host previously reported to exist exclusively as a tube isomer (T). We show that upon encapsulating various tetrahedrally shaped guests, T can reconfigure into a cage-shaped host (C) in quantitative yield. Extracting the guest affords empty C, which is metastable and spontaneously relaxes to T, and the T⇄C interconversion can be repeated for multiple cycles. Reversible toggling between two vastly different isomers paves the way toward controlling functional properties of coordination hosts “on demand”.
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