English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/53659
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:


Osmium NHC complexes from alcohol-functionalized imidazoles and imidazolium salts

AuthorsEguillor, Beatriz ; Esteruelas, Miguel A. ; García-Raboso, Jorge ; Oliván, Montserrat ; Oñate, Enrique
Issue Date2011
PublisherAmerican Chemical Society
CitationOrganometallics 30(6): 1658-1667 (2011)
AbstractThe hexahydride complex OsH6(PiPr3) 2 (1) reacts with 1-mesitylimidazole, 1-methylimidazole, 1-(2-hydroxy-2-phenylethyl)imidazole, and 1-(2-hydroxypropyl)imidazole to give the N-bound imidazole compounds OsH4(RIm)(PiPr 3)2 (R = Mes (2), Me (3), CH2CH(OH)Ph (4), CH2CH(OH)CH3 (5)) and H2. In toluene under reflux the alcohol derivatives 4 and 5 evolve into the C-bound imidazole complexes OsH3{CNHCHCHNCH=C(R)O}(PiPr3) 2 (R = Ph (6), CH3 (7)), bearing an NH wingtip. These NHC-enolate species result from the N-bound to C-bound transformation of the heterocycle and the deprotonation-dehydrogenation of the alcohol substituent. The addition of HBF4 to 6 and 7 affords the NHC-keto derivatives [OsH3{CNHCHCHNCH2C(R)=O}(PiPr3) 2]BF4 (R = Ph (8), CH3 (9)). Treatment of 1 with 3-benzyl-1-(2-hydroxy-2-phenylethyl)imidazolium tetrafluoroborate and 3-benzyl-1-(2-hydroxypropyl)imidazolium tetraphenylborate leads to the NHC-keto complexes [OsH3{CN(CH2Ph)CHCHNCH2C(R)=O}(P iPr3)2]A (A = BF4, R = Ph (10); A = BPh4, CH3 (11)), as a consequence of the direct metalation of the heterocycle and the dehydrogenation of the alcohol substituent. The deprotonation of 10 and 11 with KtBuO gives the NHC-enolate derivatives OsH3{CN(CH2Ph)CHCHNCH=C(R)O}(P iPr3)2 (R = Ph (12), CH3 (13)). The X-ray diffraction structures of 2, 6, and 10 are also reported. © 2011 American Chemical Society.
Identifiersdoi: 10.1021/om101173e
issn: 0276-7333
e-issn: 1520-6041
Appears in Collections:(ICMA) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
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.