Aqueous Heck arylation of acrolein derivatives: the role of cyclodextrin as additive

Autor: Al, Maksoud Walid, Jahjah, Mohamed, Monflier, Eric, Ponchel, Anne, Leger, Bastien, Menuel, Stéphane, Pinel, C., Djakovitch, L.
Přispěvatelé: UCCS Équipe Catalyse Supramoléculaire, Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille-Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, BIOVERT (BIOVERT), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), IRCELYON, ProductionsScientifiques, Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Organic Reactions Catalysis Society Conference
Organic Reactions Catalysis Society Conference, Mar 2014, Tucson, United States
Popis: International @ BIOVERT+CPI:LDJ; International audience; Cinnamaldehyde derivatives and 3-aryl propionic acids are important building blocks in organic synthesis. Therefore, several palladium-catalyzed procedures have been reported for their synthesis including acrolein dialkylacetal arylation [1]. However, the reaction was not selective and mixtures of aldehyde and ester were obtained those selectivity could be directed by the nature of the catalytic system. Moreover, these palladium catalysed methodologies remain linked to the use of polar organic solvents like DMF or DMAc that have been recently prohibited in most of the chemical industries. In this context, the use of alternative non-toxic solvent appears to be very attractive, water emerging as a good candidate in regards to previous industrial development. Pursuing our efforts to develop sustainable processes for fine chemical syntheses we investigated the Heck arylation of acrolein diethylacetal to cinnamaldehydes or 3-arylpropionic acids in water focusing on the selectivity. The presence of cyclodextrins (CD), known to play a positive role in large range of water phase reaction [2], was evaluated in this work both in the presence of homogeneous or heterogeneous palladium catalysts ([Pd(NH3)4Cl2] or [Pd]/NaY). Scheme 1: Products observed during the arylation of acrolein diethylacetal. Under homogeneous conditions, in the presence of NH(iPr)2 as base, 1 was the main product while cinnamaldehyde 2 was obtained preferentially in the presence of NaOAc. The addition of cyclodextrine (native or modified) has no influence on the selectivity of the reaction but slight increase of the conversion was observed. Moreover, [Pd]/NaY catalyst exhibited high activity for this reaction, while the selectivity was similar to the one observed with [Pd(NH3)4Cl2]. Interestingly, 5 successive runs were carried out and no deactivation was observed (Fig 1). Figure 1: Arylation of acrolein diethyl acetal. Reaction conditions: 3mmol PhI, 9mmol de acrolein diethyl acetal, 4.5mmol NH(i-Pr)2, 2mol% [Pd]/NaY, 100°C, 24h, 10mol% de Rame-˛-CD. Analyses of the solutions after reaction have shown that in the presence of cyclodextrins, the palladium species were stabilized, giving active species for coupling reaction.
Databáze: OpenAIRE
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