The first catalytic method for Heck alkynylation of unactivated aryl bromides (copper-free Sonogashira) in an ionic liquid:: 1 mol-% palladium/triphenylphosphane/pyrrolidine in [BMIM][BF4] as a simple, inexpensive and recyclable system
The first catalytic method for Heck alkynylation of unactivated aryl bromides (copper-free Sonogashira) in an ionic liquid:: 1 mol-% palladium/triphenylphosphane/pyrrolidine in [BMIM][BF4] as a simple, inexpensive and recyclable system
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DOI：
10.1002/ejoc.200600976
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发表时间：
2007-02-01
影响因子：
2.8
通讯作者：
Meunier, Philippe
中科院分区：
文献类型：
--
作者：
Hierso, Jean-Cyrille;Boudon, Julien;Meunier, Philippe
在此，我们报告的Heck炔基化（无铜Sonogashira）与芳基卤化物（I，Br，Cl）采用各种金属前体，叔膦和碱[BMIM]（BF 4）作为溶剂的研究。因此，我们提供了第一种方法，该方法允许在离子液体中偶联大量的底物，无论是活化的还是失活的溴化物。此外，最高效率的系统出乎意料地是最简单和更便宜的组合，其使用仅1摩尔%负载量的[Pd（eta（3）-C3 H5）Cl]（2）/PPh 3，其中吡咯烷作为碱并且不存在铜盐。空间和电子失活的溴化物轴承不同的功能基团的芳基和烷基乙炔的耦合，以及回收的可能性，使这些结果的高度兴趣的Heck和Sonogashira型反应在离子液体中的未来发展。(C)Wiley-VCH Verlag GmbH & Co.
Herein we report the studies of Heck alkynylation (copper-free Sonogashira) with aryl halides (I, Br, Cl) employing various metallic precursors, tertiary phosphanes and bases in [BMIM](BF4] as the solvent. As a result, we provide the first method that allows the coupling of a large array of substrates, either activated or deactivated bromides in an ionic liquid. Furthermore, the system of highest efficiency is unexpectedly the simplest and cheaper combination that employs [Pd(eta(3)-C3H5)Cl](2)/PPh3 at only a 1 mol-% loading with pyrrolidine as the base and in the absence of a copper salt. The coupling of sterically and electronically deactivated bromides bearing different functional groups to aryl- and alkyl acetylenes, as well as the possibility of recycling, make these results of high interest to the future development of Heck-and Sonogashira-type reactions in ionic liquids. (C) Wiley-VCH Verlag GmbH & Co.