The macrocyclization of the tetra-hydroxyphenoxy-substituted perylene bisimide 4 bearing two (R)-configured 2-octyl substituents in the imide positions by etherification with diethylene glycol ditosylate afforded both the diagonally bridged (1,7- and 6,12-linkage) and laterally bridged (1,12- and 6,7-linkage) regioisomers 6 and 7. The atropo-diastereomers of the diagonally bridged macrocycle 6 were separated by semipreparative HPLC on a chiral column, and their absolute configurations were determined by circular dichroism (CD) spectroscopy in combination with quantum chemical CD calculations. The isolated epimers (P,R,R)-6 and (M,R,R)-6 represent the first examples of diasteriomerically pure perylene bisimide atropisomers. The optical and chiroptical properties of these epimers were investigated by UV/vis, fluorescence, and CD spectroscopy, and their conformational properties have been explored by temperature-dependent 1H NMR studies.
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http://dx.doi.org/10.1021/jo070056c | DOI Listing |
Chem Commun (Camb)
January 2025
Institut für Organische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
Modulation of optical properties through smart protein matrices is exemplified by a few examples in nature such as rhodopsin (absorption wavelength tuning) and the green fluorescence protein (emission), but in general, the scope found in nature for the matrix-controlled photofunctions remains rather limited. In this review, we present cyclophane-based supramolecular host-guest complexes for which electronic interactions between the cyclophane host and mostly planar aromatic guest molecules can actively modulate excited-state properties in a more advanced way involving both singlet and triplet excited states. We begin by highlighting photofunctional host-guest systems for on-off fluorescence switching and chiroptical functions using bay-functionalized perylene bisimide cyclophanes.
View Article and Find Full Text PDFPolymers (Basel)
January 2025
Faculty of Materials Science and Engineering, Kyoto Institute of Technology, Sakyo, Kyoto 606-8585, Japan.
The transient dynamics of photocurrents for poly((4-diphenylamino)benzyl acrylate) (PDAA)-based photorefractive (PR) polymers sensitized with perylene bisimide derivative N,N'-diisopropylphenyl-1,6,7,12-tetrachloroperylene-3,4,9,10-tetracarboxyl bisimide (PBI) at various composition ratios were studied. The PR polymer included (4-(diphenylamino)phenyl)methanol (TPAOH) photoconductive plasticizer and (4-(azepan-1-yl)-benzylidene) malononitrile nonlinear optical dye as well, which are needed for inducing PR effects. All the photocurrents measured at 640 nm were well simulated by a two-trapping site model considering photocarrier generation and recombination processes of the charge transfer (CT) complex between PBI and PDAA.
View Article and Find Full Text PDFJ Org Chem
January 2025
Center for Nanosystems Chemistry (CNC), Universität Würzburg, Theodor-Boveri-Weg, 97074 Würzburg, Germany.
Chiral organic molecules with a complementing π-structure are highly desired to obtain materials with good semiconducting properties and pronounced chirality effects in the visible region. Herein, we introduce a novel design strategy to achieve an axially chiral and rigid perylene bisimide (PBI) dye by attaching the chirality-inducing 2,2'-biphenoxy moiety at one side of the bay area and the rigidity-inducing di--butylsilanediol bridge on the other side. This yielded a new bay-functionalized PBI derivative carrying the combination of a highly rigid and, simultaneously, an axially chiral perylene core.
View Article and Find Full Text PDFChemistry
December 2024
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India.
This study presents a selenium-annulated perylene bisimide (PBI-Se) stabilizing room temperature columnar hexagonal phase with exceptionally low clearing temperature. The synthesis of this Se-annulated PBI (PBI-Se) was accomplished using the reductive Cadogan cyclization method, with the introduction of swallow tails to reduce the clearing temperature and improve solubility. In addition, the charge carrier mobility of the Se-bay annulated PBI is assessed by space charge limited current (SCLC) technique and juxtaposed with PBI as well as nitrogen and sulphur-bay-annulated PBIs.
View Article and Find Full Text PDFLangmuir
December 2024
College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, PR China.
Heparin is widely used to treat thrombosis because it is an effective anticoagulant. However, excessive use of heparin can lead to an increased risk of bleeding, which makes the quantitative detection of heparin very important. An amphiphilic perylene bisimide molecule (denoted PBI-9) was developed, which presented a near-infrared emission peak at 730 nm when it was aggregated.
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