PdCl2[4,4′-bis(RfCH2OCH2)-2,2′- bipyridine] (Rf=HC4F8, HC8F16, C3F7及C10F21)之合成、構造及反應性(在氟有機二相的應用)

Synthesis, structure and reactivity of PdCl2[4,4′-bis(RfCH2OCH2)-2,2′-bipyridine] (Rf=HC4F8, HC8F16, C3F7 and C10F21) and its application in fluorous biphase system(FBS)

陳政湧(Jeng-Yung Chen)

指導教授 ： 呂良賜

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00206

摘要

我們已合成出一系列在聯吡啶的4,4′位置有兩個氟化烷基側鏈的聯吡啶配位基[4,4′-bis(RfCH2OCH2)-2,2′-bipyridine , Rf=HC4F8(1a), HC8F16(1b), C3F7(1c)及C10F21(1d)]，經由親核取代反應，由4,4′-bis(bromomethyl)-2,2′-bipyridine反應而得，並具有不錯的產率，其純化也簡易可行，所合成之產物並可用GC-MASS、NMR、FT-IR鑑定其化學結構。其後再與PdCl2(CH3CN)2反應形成聯吡啶鈀錯合物，所合成之產物可用NMR、FAB、FT-IR來鑑定。此四種新的鈀錯合物，用於催化Heck反應有不錯的催化活性，並且可以回收重複使用，八次反應後仍有很高的活性。
當聯吡啶配位基含氟量越來越高時，4,4′-bis(RfCH2OCH2)-2,2′-bipyridine(Rf= HC8F16及C10F21)，其在氟溶劑中的溶解度相較於一般有機溶劑高，於低溫下在有機溶劑中的溶解度很低，故氟/有機雙相反應，於高溫時兩相互溶進行均相催化，反應完成後降溫分層，在有機層中收集產物而在氟相層中回收催化劑。藉此我們可以在氟/有機雙相系統中有效率的催化Heck反應，並以控制溫度的方式輕易地回收催化劑。

關鍵字

氟有機二相 ； 氟化聯吡啶配位基

並列摘要

We have synthesized a series of 4,4′ perfluoro-alkylated bipyridine ligands[4,4′- bis(RfCH2OCH2)-2,2′-bipyridine , Rf=HC4F8(1a), HC8F16(1b), C3F7(1c) and C10F21 (1d)] by nucleophilic substitution reactions. The reaction of fluorinated alkoxide on 4,4′-bis(bromomethyl)-2,2′-bipyridine results in the systheses of these four fluorinated ligands. These reactions are high yieldings and purification is easy. The structures are analyzed by GC-MASS、NMR、FT-IR etc. These bipyridyl palladium complexes were synthesized by bipyridine ligand reacting with PdCl2(CH3CN)2. The Pd complexes are characterized by NMR、FAB、FT-IR. These four complexes were used as catalysts
for Heck reactions with high catalytic activities. The catalytic abilities have been tested up to eight time without major loss of activities.
When the fluorine content of ligands approached 60% ,eg. 4,4′-bis(RfCH2OCH2)- 2,2′-bipyridine (Rf=HC8F16 and C10F21), they showed higher affinity in the fluorous solvent than for common organic solvent, and they had little or no solubility for organic solvent at low temperature. Fluorous biphase system(FBS) becomes homogeneous at elevated temperature and showed two phases at low temperature. By using FBS we could get product from organic phase and recover catalyst from fluorous phase. For example, the Heck reactions had been demonstrated using the fluorous biphase system.

並列關鍵字

FBS ； perfluoro bipyridine ligand

參考文獻

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