English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/37892
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Experimental and theoretical studies on the asymmetric cyanosilylation of C2-symmetric hydrazones

AuthorsRos, Abel ; Díez, Elena; Marqués-López, Eugenia ; Martín-Zamora, Eloísa; Vázquez, Juan; Iglesias-Sigüenza, Javier; Pappalardo, Rafael R.; Álvarez, Eleuterio ; Lassaletta, José M. ; Fernández, Rosario
KeywordsAsymmetric cyanosilylation
Hydrazino nitriles
Issue Date6-May-2008
CitationTetrahedron Asymmetry 19(8): 998-1004 (2008)
AbstractThe Et2AlCl-promoted asymmetric cyanosilylation of (2S,5S)-1-amino-2,5-diphenylpyrrolidine-derived aliphatic hydrazones affords the corresponding hydrazinonitriles with high diastereoselectivity (dr 91:9 to >99:1). The resolving properties of the auxiliary allowed the isolation of the adducts as single diastereoisomers (dr >99:1) in good yields (80–84%) after chromatography. Ab initio MO calculations indicated that the formation of the hydrazone-promoter complex inhibits n→π conjugation and increases the nucleophilicity of the dialkylamino nitrogen, enabling the basic activation of TMSCN. The calculated geometries for these complexes show the shielding of the Si face of the CN bond by one of the phenyl groups in the auxiliary, providing an explanation for the observed absolute configuration.
Description7 páginas, 3 figuras, 3 tablas, 1 esquema.
Publisher version (URL)http://dx.doi.org/10.1016/j.tetasy.2008.03.020
Appears in Collections:(IIQ) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.