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http://dx.doi.org/10.18419/opus-1072
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DC Element | Wert | Sprache |
---|---|---|
dc.contributor.author | Effenberger, Franz | de |
dc.contributor.author | Agster, Wolfgang | de |
dc.contributor.author | Fischer, Peter | de |
dc.contributor.author | Jogun, Kurt H. | de |
dc.contributor.author | Stezowski, John J. | de |
dc.contributor.author | Daltrozzo, Ewald | de |
dc.contributor.author | Kollmannsberger- von Nell, Georg | de |
dc.date.accessioned | 2009-07-29 | de |
dc.date.accessioned | 2016-03-31T07:47:34Z | - |
dc.date.available | 2009-07-29 | de |
dc.date.available | 2016-03-31T07:47:34Z | - |
dc.date.issued | 1983 | de |
dc.identifier.other | 310656281 | de |
dc.identifier.uri | http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-42955 | de |
dc.identifier.uri | http://elib.uni-stuttgart.de/handle/11682/1089 | - |
dc.identifier.uri | http://dx.doi.org/10.18419/opus-1072 | - |
dc.description.abstract | Reaction of the activated halonitrobenzenes 2a-f with the bis- and tris(dialkylamino)benzenes 1a-e affords, via a direct nucleophilic substitution, the highly substituted biphenyls 3a-o; the lesser substituted biphenyls 5 and 6 were prepared by an Ullmann reaction. All these biphenyls are deeply colored; the dark red color can be assigned to an intramolecular charge transfer. A crystal structure determination was carried out for 2,4,6-tripyrrolidino-2',4',6'-trinitrobiphenyl (3a): space group C2/c, a = 16.071 (2) A, b = 14.545 (1) A, c = 20.177 (2) A, {3 = 91.361 (9)°, Z = 8 (temperature ≈ 120 K). The dihedral angle between the two arene rings was found to be only 52.5°, despite the four bulky substituents in the o,o'-positions. With this far-from-orthogonal torsional angle about the biphenyl linkage, the strong intramolecular charge transfer from the π system of the donor into the π system of the acceptor arene becomes easily understandable. A PPP calculation with the torsional angles taken from the X-ray structure analysis satisfactorily reproduces the experimental absorption spectrum of 3a. The shift of the long-wavelength absorption between the individual biphenyls 3a-o, 5, and 6 likewise is accounted for satisfactorily by the calculation; it depends primarily on the intrinsic donor strength of the different NR2 moieties (pyrrolidino > dimethylamino > piperidino > morpholino). The IH NMR spectra (in dilute solution) likewise mirror this gradation in Nr2 donor capacity; they also show that steric hindrance at the biphenyl linkage is mainly the result of interaction between the o-dialkylamino groups and the C6 skeleton of the acceptor arene. This is borne out by the crystal structure analysis. | en |
dc.language.iso | en | de |
dc.rights | info:eu-repo/semantics/openAccess | de |
dc.subject.classification | Elektrophile Substitution , Biphenylderivate | de |
dc.subject.ddc | 540 | de |
dc.title | Synthesis, structure, and spectral behavior of donor acceptor substituted biphenyls | en |
dc.type | article | de |
dc.date.updated | 2009-10-01 | de |
ubs.fakultaet | Fakultät Chemie | de |
ubs.institut | Institut für Organische Chemie | de |
ubs.opusid | 4295 | de |
ubs.publikation.source | Journal of Organic Chemistry 48 (1983), S. 4649-4658. URL http://dx.doi.org./10.1021/jo00172a040 | de |
ubs.publikation.typ | Zeitschriftenartikel | de |
Enthalten in den Sammlungen: | 03 Fakultät Chemie |
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eff145.pdf | 951,31 kB | Adobe PDF | Öffnen/Anzeigen |
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