English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/111845
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

Chiral brønsted acid catalysts. Activation of methyl 3,3,3-trifluoropyruvate by hydroxymethylpyridine-containing half-sandwich complexes

AutorCarmona, Daniel ; Lamata, M. Pilar ; Sánchez, Antonio; Pardo, Pilar ; Rodríguez, Ricardo ; Ramírez, Paola; Lahoz, Fernando J. ; García-Orduña, P. ; Oro, Luis A.
Fecha de publicación2014
EditorAmerican Chemical Society
CitaciónOrganometallics 33(15): 4016-4026 (2014)
ResumenThe coordinated OH group in cationic complexes [(ηn-ring) M(NOH)(Solv)][SbF6] and [(ηn-ring)M(NOH){(R)-P1}] [SbF6]2 ((ηn-ring)M = (η5- C5Me5)Rh, (η5-C5Me 5)Ir, (η6-p-MeC6H4iPr)Ru; NOH = hydroxypyridine ligand; (R)-P1 = (R)-monophos) is deprotonated by Na 2CO3, rendering bi- or mononuclear compounds of formulas [{(ηn-ring)M(κ2N,O-μ-O-NO} 2][SbF6]2 and [(ηn-ring)M(NO) {(R)-P1}][SbF6], respectively. The complexes have been characterized by analytical and spectroscopic means, including the determination of the crystal structures of [{(ηn-ring)M(κ2N,O-μ-O- NO}2][SbF6]2 (NOH = NOH-1, (ηn- ring)M = (η5-C5Me5)Rh, 8a; (η6-p-MeC6H4iPr)Ru, 8c) and [(η5-C5Me5)Ir(NO){(R)-P1}][SbF 6] (NOH = (R)-NOH-2; (R)-11b) by X-ray diffractometric methods. In complexes [(ηn-ring)M(NOH)(P)][SbF6]2 (P* = chiral phosphoramidite ligand) the proton of the coordinated hydroxypyridine ligand is able to activate the carbonyl group of methyl 3,3,3-trifluoropyruvate toward the Friedel-Crafts addition of indoles. In most cases, quantitative conversion is achieved in a few minutes, at -70 °C, with an ee of up to 82%. NMR data support the activation of the pyruvate by interaction between its carbonyl oxygen and the OH group of the coordinated hydroxymethylpyridine. Therefore, the metallic complexes act as Lewis acid assisted Brønsted acid catalysts. © 2014 American Chemical Society.
URIhttp://hdl.handle.net/10261/111845
DOI10.1021/om5005463
Identificadoresdoi: 10.1021/om5005463
issn: 0276-7333
e-issn: 1520-6041
Aparece en las colecciones: (ISQCH) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
accesoRestringido.pdf15,38 kBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo
 

Artículos relacionados:


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.