Impact of cyclodextrins on the behavior of amphiphilic ligands in aqueous organometallic catalysis
نویسندگان
چکیده
In this study, we showed that the addition of randomly modified β-cyclodextrin (RAME-β-CD) in aqueous medium could have a beneficial impact on the catalytic performances of phosphane-based aggregates in the Pd-catalyzed cleavage of allyl carbonates (Tsuji-Trost reaction). The RAME-β-CD/phosphane supramolecular interactions helped explain the catalytic results. The presence of RAME-β-CD in the aqueous compartment improved the phosphane-based aggregate dynamics. The exchanges between the hydrophobic substrate-containing aggregate core and the catalyst-containing aqueous phase were then greatly favored, resulting in an increase in the catalytic performances.
منابع مشابه
Chemically Modified Cyclodextrins: An Attractive Class of Supramolecular Hosts for the Development of Aqueous Biphasic Catalytic Processes
During these last years, cyclodextrins have contributed greatly to the development of catalytic processes in water. These cyclic oligosaccharides composed of 6(), 7() or 8() glucopyranose units improve the mass transfer in aqueous-organic two-phase systems and are useful compounds to design new catalysts. Thus, chemically modified cyclodextrins can be used to: (i) increase significantly the ...
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