کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1315253 | 976014 | 2009 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Synthesis of bis(polyfluoroalkylated)imidazolium salts as key intermediates for fluorous NHC ligands Synthesis of bis(polyfluoroalkylated)imidazolium salts as key intermediates for fluorous NHC ligands](/preview/png/1315253.png)
1,3-Bis(polyfluoroalkyl)- and 1-mesityl-3-(polyfluoroalkyl)imidazolium salts differing in the length of a polyfluorinated chain and a non-fluorinated spacer were synthesized as key building blocks for fluorous NHC (N-heterocyclic carbene) ligands. A new approach using polyfluoroalkyl triflates instead of the corresponding iodides was employed allowing fine tailoring of fluorous properties, as well as of the electron density of the imidazolium ring. Using bis(polyfluoroalkylated)imidazolium salt, a fluorous analogue of the PEPPSI™ catalyst was synthesized and its structure confirmed by X-ray diffraction. The catalyst was employed in model Heck and Suzuki couplings with moderate yields, however, its recycle was not successful. Fluorophilicity of bis(polyfluoroalkylated)imidazolium salts was found to be surprisingly low compared with the analogous perfluoropolyether-based salts.
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Journal: Journal of Fluorine Chemistry - Volume 130, Issue 10, October 2009, Pages 966–973