One-Pot Desilylation/Dimerization of Terminal Alkynes by Ruthenium and Acid-Promoted (RAP) Catalysis
作者:Chiara Pasquini、Mauro Bassetti
DOI:10.1002/adsc.201000347
日期:2010.10.4
promoted by the (p-cymene)ruthenium dichloride dimer/acetic acid system [RuCl2(p-cymene)]2/AcOH} can be performed starting from the trimethylsilylethynyl derivatives (12 substrates), deprotected in situ, to afford 1,4-disubstituted 1-en-3-ynes with high regio- and (E)-stereoselectivity, at room temperature. The extension of this unprecedented two-reaction sequence to a diyne substrate affords a fluorene-based
(p- cymene)二氯化钌二聚体/乙酸体系[RuCl 2(p- cymene)] 2 / AcOH}促进的末端芳基炔烃的二聚反应可从就地脱保护的三甲基甲硅烷基乙炔基衍生物(12种底物)开始进行,以提供具有高区域和(E的1,4-二取代的1-en-3-ynes)-立体选择性,在室温下。将该前所未有的两个反应序列延伸至二炔基底,得到了芴基共轭低聚物。脱甲二聚反应过程产生的反应混合物使苯乙炔的其他等分试样二聚。一锅法方案由于乙酸盐的存在而缩短了反应时间,乙酸盐增加了活性催化物质的浓度,其中乙酸盐配体充当朝向键合炔的碱。钌源被转化为新的三触六-1,3-dien-5-yn-3-yl络合物,该络合物是由烯炔产物和末端炔烃的金属辅助偶联形成的,并且仍保持催化活性。选择性,持久性,中等和官能团的相容性是从三氯甲烷获得的催化体系的关键特征。在一锅条件下,对-异丙基钌二聚体。