Status: Bibliographieeintrag
Standort: ---
Exemplare:
---
| Online-Ressource |
Verfasst von: | Menning, Sebastian [VerfasserIn]  |
| Krämer, Maximilian [VerfasserIn]  |
| Rominger, Frank [VerfasserIn]  |
| Dreuw, Andreas [VerfasserIn]  |
| Bunz, Uwe H. F. [VerfasserIn]  |
Titel: | Bridged tolanes |
Titelzusatz: | a twisted tale |
Verf.angabe: | Sebastian Menning, Maximilian Krämer, Andrew Duckworth, Frank Rominger, Andrew Beeby, Andreas Dreuw, and Uwe H. F. Bunz |
Umfang: | 8 S. |
Fussnoten: | Gesehen am 11.12.2017 |
Titel Quelle: | Enthalten in: The journal of organic chemistry |
Jahr Quelle: | 2014 |
Band/Heft Quelle: | 79(2014), 14, S. 6571-6578 |
ISSN Quelle: | 1520-6904 |
Abstract: | The rotational motion of tolanes along their acetylene axis is not fully understood. What happens to the optical and electronic properties if the tolane backbone is forced into a twisted conformation? Several tethers were investigated to obtain tolanophanes, fixing the torsion angle of the two phenyl rings. X-ray crystal structures revealed tether-specific torsion angles in the solid state. The absorption, emission, and excitation spectra were recorded. Twisted tethered tolane conformers showed blue-shifted absorption; emission spectra were all torsionally independent and identical. The tethered tolanes were embedded in a rigid matrix by freezing to 77 K; well-resolved emission spectra were recorded for planar tolanes, but for twisted systems unexpectedly long-lived phosphorescence was observed. How is this triplet emission explained? Quantum chemical calculations (TDDFT/cam-B3LYP/6-31G*) of the unsubstituted tolane showed that intersystem crossing (ISC) is favored with largespin-orbit coupling, which occurs when the molecular orbitals are orthogonal to each other; this is the case at the crossing of S1/T7. Also, a small energy difference between singlet and triplet states is required; we found that ISC can favorably take place at four crossings: S1/T6, S1/T7, S1/T8,9, S1/T10. |
DOI: | doi:10.1021/jo5010235 |
URL: | Bitte beachten Sie: Dies ist ein Bibliographieeintrag. Ein Volltextzugriff für Mitglieder der Universität besteht hier nur, falls für die entsprechende Zeitschrift/den entsprechenden Sammelband ein Abonnement besteht oder es sich um einen OpenAccess-Titel handelt.
Verlag: http://dx.doi.org/10.1021/jo5010235 |
| DOI: https://doi.org/10.1021/jo5010235 |
Datenträger: | Online-Ressource |
Sprache: | eng |
K10plus-PPN: | 1566208890 |
Verknüpfungen: | → Zeitschrift |
Bridged tolanes / Menning, Sebastian [VerfasserIn] (Online-Ressource)
68199930