Novel Metal- and Mineral-Acid–Free Synthesis of Organic Ammonium Tribromides and Application of Ethylenephenanthrolium Bistribromide for Bromination of Active Methylene Group of 1,3-Diketones and β-Ketoesters
作者:Rupa Rani Dey、Bappi Paul、Siddhartha Sankar Dhar
DOI:10.1080/00397911.2014.979509
日期:2015.3.19
mineral acid or metal catalyst/promoters. A variety of tribromides are synthesized in very good yields including a hitherto unknown reagent, 1,10-(ethane-1, 2-diyl)phenanthrolinediium bistribromide (EPDBT). EPDBT is investigated as brominating agent and found to be highly effective for selective bromination of active methylene groups of a variety of 1,3-diketones and β-ketoesters. GRAPHICAL ABSTRACT
摘要 描述了一种从相应的溴化物制备有机三溴化铵 (OATBs) 的新方法。季铵溴化物 (QABs) 和 N,N'-杂环二溴化物分别在 2 和 4 当量 KBr 存在下被间氯过苯甲酸 (MCPBA) 有效氧化为相应的单三溴化物和双溴化物。反应在水性介质中进行,不使用任何无机酸或金属催化剂/促进剂。多种三溴化物以非常好的收率合成,包括迄今为止未知的试剂,1,10-(乙烷-1, 2-二基)菲咯啉二溴化 (EPDBT)。EPDBT 被研究为溴化剂,发现它对于选择性溴化各种 1,3-二酮和 β-酮酯的活性亚甲基非常有效。图形概要