Strukturen ladungsgestörter oder räumlich überfüllter Moleküle, 108 [1] Strukturänderungen bei der Zweifach-Reduktion von Tetraphenyl-p-chinodimethan zu seinem Dianion
Structures of Charge-Perturbed or Sterically Overcrowded Molecules, 108 [1] Structural Changes of Tetraphenyl-p-quinodim ethane on Twofold Reduction to its Dianion
- The two-electron reduction of tetraphenyl-p-quinodimethane M via its radical anion M⊖ to its dianion M⊖⊖ is explored both by cyclovoltammetry and ESR/ENDOR spectroscopy. Contact of the diglyme solution with added 15-crown-5 under aprotic conditions with a sodium metal mirror yields black crystals of a solvent-separated contact ion triple [M⊖⊖][Na⊕(OCH2CH2)5(H3CO(CH2CH2O)2CH3)]2. The two-electron-insertion into the pquinodimethane derivative R2C⊖=C(HC=CH)2C=CR2 changes its structure drastically to that of a twofold carbanion substituted benzene, R2C⊖ -(C6H4)- ⊖CR2. MNDO calculations provide a rationale for both the tremendous solvation of a Na⊕ center coordinated to seven oxygen centers of 15-crown-5 and of one diglyme molecule and the structural changes as well as the charge distribution in the unique Tetraphenyl-p-quinodimethane dianion (H5C6)2C⊖-(C6H4)- ⊖C(C6H5)2, in which the two negative charges are largely localized at the carbanion center of the benzene -substituents.
Author: | Hans BockGND, Claudia Arad, Christian NätherORCiDGND, Ilka Göbel, Andreas John |
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URN: | urn:nbn:de:hebis:30:3-742045 |
DOI: | https://doi.org/10.1515/znb-1996-1004 |
ISSN: | 1865-7117 |
ISSN: | 0932-0776 |
Parent Title (German): | Zeitschrift für Naturforschung, B |
Publisher: | Verlag der Zeitschrift für Naturforschung |
Place of publication: | Tübingen |
Document Type: | Article |
Language: | German |
Date of Publication (online): | 2023/07/13 |
Year of first Publication: | 1996 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2023/09/23 |
Tag: | Crystal Structure; Cyclovoltammetry; ESR/ENDOR Measurements; MNDO Calculations; Tetraphenyl-p-quinodimethane Dianion |
Volume: | 51 |
Issue: | 10 |
Page Number: | 9 |
First Page: | 1391 |
Last Page: | 1399 |
HeBIS-PPN: | 512770301 |
Institutes: | Biochemie, Chemie und Pharmazie / Biochemie und Chemie |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Sammlungen: | Universitätspublikationen |
Licence (German): | Creative Commons - Namensnennung-Nicht kommerziell-Keine Bearbeitung 3.0 |