ISSN:
1572-9028
Keywords:
supported aqueous phase catalysts
;
biphasic water/organic solvent
;
palladium
;
allylic substitution
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The supported aqueous phase methodology was applied to the catalytic system Pd(OAc)2/5TPPTS, a catalyst precursor of the Trost–Tsuji reaction. The characterization of the solid by 31P MAS NMR spectroscopy confirms the reduction by the phosphines of Pd(II) to Pd(0) as Pd(TPPTS)3. The catalytic properties of this solid were determined for the allylic substitution of (E)-cinnamyl ethyl carbonate by nucleophiles such as ethyl acetoacetate, dimethyl malonate, morpholine, phenol and 2-mercaptopyridine and were compared to those of the same catalytic system in a biphasic water/nitrile medium. Having demonstrated the absence of palladium leaching and having solved the problem of water leaching from the solid into the organic solvent, the SAP Pd catalyst was engaged with success in a continuous flow experiment, demonstrating the possibility to reach a productivity superior to 2200 moles of carbonate selectively converted per mole of palladium within 11 h.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009082216524
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