Options
Neier, Reinhard
Nom
Neier, Reinhard
Affiliation principale
Fonction
Professeure ordinaire
Email
Reinhard.Neier@unine.ch
Identifiants
Résultat de la recherche
Voici les éléments 1 - 4 sur 4
- PublicationMétadonnées seulementTandem nucleophilic addition/Diels-Alder reaction of N-butadienyl N,O-ketene silyl acetals with C-60: Stereoselective formation of bicyclic octahydroquinoline-1,2,3,4-tetrahydrobuckminsterfullerenes and combined NMR spectroscopic and computational evaluation of the functionalization reactions(1999)
;Rubin, Yves ;Ganapathi, Padma ;Franz, Andreas ;An, Yi-Zhong ;Qian, WenyuanWe have studied the reactivity of the N,O-ketene N-1,3-butadienyl-N-alkyl-O-silyl acetals 1a-e with C-60 proceeding through a tandem process to give the adducts 2a-e, The addition order of these tandem reactions has been evaluated. The initial nucleophilic Michael-like addition of the electron-rich N,O-ketene acetal moiety proceeds unusually fast at 25 degrees C, followed by an intramolecularly accelerated Diels-Alder step that is highly diastereoselective. The structures of compounds 2a-e were determined from the H-1 and C-13 NMR shifts and from II-II coupling patterns, while their stereochemistry was deduced from 2D T-ROESY NMR experiments. The proposed mechanism for the nucleophilic addition involves single electron transfer followed by radical anion-radical cation recombination. Computational investigations of the reaction pathways, transition states, and conformational energies have been carried out to corroborate the experimental data. - PublicationAccès libreTandem Nucleophilic Addition/Diels-Alder Reaction of N-Butadienyl N,O-Ketene Silyl Acetals with C60: Stereoselective Formation of Bicyclic Octahydroquinolino-1,2,3,4-Tetrahydrobuckminsterfullerenes and Combined NMR Spectroscopic and Computational Evaluation of the Functionalization Reactions(1999)
;Rubin, Yves ;Ganapathi, Padma S. ;Franz, Andreas ;An, Yi-Zhong ;Qian, WenyuanAbstract: We have studied the reactivity of the N,0-ketene N-l,3-butadienyl-N-alkyl-0-silyl acetals 1a-e with C60 proceeding through a tandem process to give the adducts 2a-e. The addition order of these tandem reactions has been evaluated. The initial nucleophilic Michael-like addition of the electron-rich N,O-ketene acetal moiety proceeds unusually fast at 25°C, followed by an intramolecularly accelerated Diels-Alder step that is highly diastereoselective. The structures of compounds 2a-e were determined from the 1H and 13C NMR shifts and from H - H coupling patterns, while their stereochemistry was deduced from 2D T-ROESY NMR experiments. The proposed mechanism for the nucleophilic addition involves single electron transfer followed by radical anion - radical cation recombination. Computational investigations of the reaction pathways, transition states, and conformational energies have been carried out to corroborate the experimental data. - PublicationMétadonnées seulementPreparation of N-alkylketene-N-butadienyl-N,O-silyl acetals(1996)
;Franz, Andreas ;Eschler, Pierre Yves ;Tharin, Manuel; The synthesis of a series of dienamides 5a-j using Oppolzer's method is described. Using Rathke's method the ketene N,O-silyl acetals 6a-j can be obtained in good yield from the corresponding dienamides. The ketene acetals are obtained free of base and free of salts. They are stable and can be stored at - 20 degrees C. The new dienes are useful reagents for tandem reactions. - PublicationAccès librePreparation of N-Alkylketene-N-Butadienyl-N,O-Silyl Acetals(1996)
;Franz, Andreas ;Eschler, Pierre-Yves ;Tharin, Manuel; The synthesis of a series of dienamides 5a-j using Oppolzer’s method is described. Using Rathke’s method the ketene N,O-silyl acetals 6a-j can be obtained in good yield from the corresponding dienamines. The ketene acetals are obtained free of base and free of salts. They are stable and can be stored at -20°C. The new dienes are useful reagents for tandem reactions.