An examination of the palladium/Mor-DalPhos catalyst system in the context of selective ammonia monoarylation at room temperature.
Chemistry
; 19(6): 2131-41, 2013 Feb 04.
Article
en En
| MEDLINE
| ID: mdl-23293095
ABSTRACT
An examination of the [{Pd(cinnamyl)Cl}(2)]/Mor-DalPhos (Mor-DalPhos = di(1-adamantyl)-2-morpholinophenylphosphine) catalyst system in Buchwald-Hartwig aminations employing ammonia was conducted to better understand the catalyst formation process and to guide the development of precatalysts for otherwise challenging room-temperature ammonia monoarylations. The combination of [{Pd(cinnamyl)Cl}(2)] and Mor-DalPhos afforded [(κ(2)-P,N-Mor-DalPhos)Pd(η(1)-cinnamyl)Cl] (2), which, in the presence of a base and chlorobenzene, generated [(κ(2)-P,N-Mor-DalPhos)Pd(Ph)Cl] (1 a). Halide abstraction from 1 a afforded [(κ(3)-P,N,O-Mor-DalPhos)Pd(Ph)]OTf (5), bringing to light a potential stabilizing interaction that is offered by Mor-DalPhos. An examination of [(κ(2)-P,N-Mor-DalPhos)Pd(aryl)Cl] (1 b-f) and related precatalysts for the coupling of ammonia and chlorobenzene at room temperature established the suitability of 1 a in such challenging applications. The scope of reactivity for the use of 1 a (5â
mol %) encompassed a range of (hetero)aryl (pseudo)halides (X = Cl, Br, I, OTs) with diverse substituents (alkyl, aryl, ether, thioether, ketone, amine, fluoro, trifluoromethyl, and nitrile), including chemoselective arylations.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Paladio
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Sulfuros
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Complejos de Coordinación
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Aminas
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Halógenos
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Amoníaco
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Cetonas
Idioma:
En
Revista:
Chemistry
Asunto de la revista:
QUIMICA
Año:
2013
Tipo del documento:
Article
País de afiliación:
Canadá
Pais de publicación:
ALEMANHA
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ALEMANIA
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DE
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DEUSTCHLAND
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GERMANY