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“Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method for Homogeneous Fluorous Catalysts. Latest CENs. Biffis, A. et al . Org . Lett . 1998, 7, 1841. “fluorous ponytails” : (CH 2 ) m (CF 2 ) n -1 CF 3. Co-cat : Co{OOC(CH 2 ) 2 (CF 2 ) 7 CF 3 } 2 ; C 6 F 14 : $17.6 (10ml).
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“Catalyst-on-a-Tape”—Teflon: A New Delivery and Recovery Method for Homogeneous Fluorous Catalysts
Latest CENs Biffis, A. et al. Org. Lett. 1998, 7, 1841
“fluorous ponytails” : (CH2)m(CF2)n-1CF3 Co-cat : Co{OOC(CH2)2(CF2)7CF3}2 ; C6F14 : $17.6 (10ml) Ru-cat : K[Ru(C7F15COCHCOC7F15)2] ; C8F14Br : $45 (1 g) Horvath, I. T. et al. Acc. Chem. Res. 1998, 31, 641
liquid/liquid phase separation Dinh, L. D. et al. New. J. Chem. 2005, 29, 173
Reaction for four cycles • As opposed to leaching • Some intrinsic problem with the recycling method
Effect of Teflon • All reactants • except • PhMe2SiH • are added; • (b) The mixture • is heated to • 55 °C; • (c) The tape is • removed; • (d) The • PhMe2SiH is • added.
Results • “catalyst-on-a-tape” 的系統提供了許多反應上的好處,也可以減少對環境的污染。 • 氟的化合物提供一個最合適的反應條件或適用於某些特定的反應,可以應用在工業上面。
Synthesis for catalyst Gladysz, J. A. et al. J. Am. Chem.Soc. 1999, 121, 2696
including the homogeneous oxidation of alcohols and alkenols and the epoxidation of alkenes." Friedel-Crafts acylations and esterifications. • a chelating solvent such as tetrahydrofuran (THF) • Reactions can be catalyzed under monophasic conditions at the high-temperature limit, and the products and catalyst can be separated under biphasic conditions at the low-temperature limit highly electron-withdrawing perfluoroalkyl groups C6F6/CF3C6H5 solution PhSiH(Me)2 : moisture sensitive(5g/$20)
Epoxidation Esterification Friedel-Crafts acylations