Synthesis of novel room temperature chiral ionic liquids: application as reaction media for the heck arylation of aza-endocyclic acrylates

Journal of the Brazilian Chemical Society

Julio C. Pastre²  Yves Génisson¹  Nathalie Saffon¹  Jany Dandurand¹  Carlos R. D. Correia² 

[1] ,Universidade Estadual de Campinas Instituto de Química Campinas SP ,Brazil

关键词: ionic liquids;    chiral ionic liquids;    Heck arylation;    arenediazonium salts;    aryl iodides;   

DOI  :  10.1590/S0103-50532010000500009

来源: SciELO

【 摘 要 】

New achiral and chiral RTILs were prepared using novel and/or optimized synthetic routes. These new series of imidazolinium, imidazolium, pyridinium and nicotine-derived ionic liquids were fully characterized including differential scanning calorimetry (DSC) analysis. The performance of these achiral and chiral room temperature ionic liquids (RTILs) was demonstrated by means of the Heck arylation of endocyclic acrylates employing arenediazonium salts and aryl iodides. The Heck arylations performed in the presence of these ionic entities, either as a solvent or as an additive, were effective leading to complete conversion of the substrate and good to excellent yield of the Heck adduct. In spite of the good performances, no asymmetric induction was observed in any of the cases studied. Two new diastereoisomeric NHC-palladium complexes were prepared in good yields from a chiral imidazolium salt and their structure characterized by X-ray diffraction. Overall, the Heck arylations employing arenediazonium tetrafluoroborates in RTILs were more effective than the traditional protocols employing aryl iodides in terms of reactivity and yields.

【 授权许可】

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