Voronova Krisztina, Homolya Levente, Udvardy Antal, Bényei Attila C, Joó Ferenc
Department of Physical Chemistry, University of Debrecen, Egyetem tér 1, H-4032 Debrecen (Hungary); Current address: Department of Chemistry, University of the Pacific, 3601 Pacific Avenue, Stockton, CA 95211 (USA).
ChemSusChem. 2014 Aug;7(8):2230-9. doi: 10.1002/cssc.201402147. Epub 2014 Jul 3.
New sulfonated tetrahydrosalen-type ligands and their water-soluble palladium(II) complexes have been synthesized. The palladium(II) complexes catalyze the Sonogashira coupling (23 examples) of various aryl halides (including chloroarenes) with terminal alkynes, with good to excellent conversions under mild conditions (80°C, air, no Cu(I) cocatalyst) in aqueous-organic mixtures and turnover frequencies of up to 2790 h(-1) . Under optimized reaction conditions to minimize environmental contamination, diphenylacetylenes can be isolated in 76-98% yield. The aqueous catalyst solution can be recycled four times with decreasing activity; however, yields between 93 and 98% can still be achieved with extended reaction times. Several water-insoluble products can be isolated in excellent yield by simple filtration and purification by washing with water; this method is used, for the first time, for this type of C-C coupling procedure.
新型磺化四氢萨伦型配体及其水溶性钯（II）配合物已被合成。钯（II）配合物催化各种芳基卤化物（包括氯代芳烃）与端炔的Sonogashira偶联反应（23个实例），在温和条件下（80°C，空气，无Cu（I）助催化剂）于水-有机混合溶剂中具有良好至优异的转化率，周转频率高达2790 h⁻¹。在优化的反应条件下以尽量减少环境污染时，二苯乙炔可以76 - 98%的产率分离得到。水性催化剂溶液可以循环使用四次，活性虽有所降低，但延长反应时间仍可实现93%至98%的产率。通过简单过滤和水洗纯化，可以以优异的产率分离出几种水不溶性产物；此方法首次用于此类碳-碳偶联过程。
