Synthese und Konfigurationszuordnung der Stereoisomeren von (3-Methyl-2-pentenyliden)triphenylphosphoran
作者： Rainer Bausch , Borislav Bogdanvić , Herbert Dreeskamp , Johan B. Koster
DOI: 10.1002/JLAC.197419741011
关键词:
摘要: Die Synthese von (3-Methyl-2-pentenyliden)triphenylphosphoran (1) aus Diisobutylaluminium-2-methylbutylidenamid (2) und Methylentriphenylphosphoran liefert die beiden Stereoisomeren (1a 1b) im Verhaltnis ca. 70:30. Ihre Zuordnung geschieht sowohl durch stereoselektive als auch NMR-Spektroskopie aufgrund bekannter Abhangigkeiten der Kopplungen HH′ CH sowie des Kern-Overhauser-Effektes Molekulgeometrie. Diese Methoden ergeben ubereinstimmend, das dem Hauptisomeren E-Struktur 1a zuzuordnen ist. Synthesis and Determination of Configuration the Stereoisomers (3-Methyl-2-pentenylidene)-triphenylphosphorane The synthesis (3-methyl-2-pentenylidene)triphenylphosphorane from diisobutylaluminium 2-methylbutylideneamide methylenetriphenylphosphorane leads to isolation two stereoisomers in ratio 70: 30. The assignment structure is solved by methods: a stereoselective NMR spectroscopy based upon known variations coupling constants nuclear Overhauser effect with molecular structure. All methods concur showing that major isomer possesses E-structure 1a.
sci-hub.se 参考文章(19)
J.A. Pople, D.P. Santry, A molecular orbital theory of hydrocarbons Molecular Physics. ,vol. 7, pp. 269- 286 ,(1964) , 10.1080/00268976300101031
John B. Siddall, M. Biskup, J. H. Fried, Synthetic studies on insect hormones. VIII. Stereospecific synthesis of trisubstituted olefins from organocopper reagents and acetylenes Journal of the American Chemical Society. ,vol. 91, pp. 1853- 1854 ,(1969) , 10.1021/JA01035A046
Erich Sackmann, Herbert Dreeskamp, Untersuchung der indirekten Kernspinkopplung zwischen Protonen und Kohlenstoff-13 über mehrere Bindungen Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. ,vol. 21, pp. 2005- 2022 ,(1965) , 10.1016/0371-1951(65)80218-1
Elias J. Corey, John A. Katzenellenbogen, Stereospecific synthesis of trisubstituted and tetrasubstituted olefins. Conjugate addition of dialkylcopper-lithium reagents to .alpha.,.beta.-acetylenic esters Journal of the American Chemical Society. ,vol. 91, pp. 1851- 1852 ,(1969) , 10.1021/JA01035A045
K. Hildenbrand, H. Dreeskamp, Notizen: NMR-Kopplungskonstanten in freien und komplexierten phosphororganischen Liganden / NMR Coupling Constants in Free and Complexed Phosphororganic Ligands Zeitschrift für Naturforschung B. ,vol. 28, pp. 226- 228 ,(1973) , 10.1515/ZNB-1973-3-430
Hubert Schmidaur, Wolfgang Tronich, Reindarstellung und Eigenschaften von Trialkyl-alkyliden-phosphoranen Chemische Berichte. ,vol. 101, pp. 595- 603 ,(1968) , 10.1002/CBER.19681010229
Martin Karplus, Contact Electron‐Spin Coupling of Nuclear Magnetic Moments The Journal of Chemical Physics. ,vol. 30, pp. 11- 15 ,(1959) , 10.1063/1.1729860
D. John FAULKNER, Stereoselective Synthesis of Trisubstituted Olefins Synthesis. ,vol. 1971, pp. 175- 189 ,(1971) , 10.1055/S-1971-21691
Aksel A. Bothner-By, W. P. Trautwein, Nuclear magnetic resonance studies of phosphate esters. I. Conformational study of trisneopentyl phosphate and tris(.beta.-chloroethyl) phosphate Journal of the American Chemical Society. ,vol. 93, pp. 2189- 2192 ,(1971) , 10.1021/JA00738A016
Roland Köster, Dragomir Simić, Maximilian A. Grassberger, Zur Darstellung salzfreier Trialkyl-alkylidenphosphorane Justus Liebigs Annalen der Chemie. ,vol. 739, pp. 211- 219 ,(1970) , 10.1002/JLAC.19707390127