New and Efficient Synthesis of Pyrrolo[3,2-<i>b</i>]pyrrole-2,5-diones by Double-Anion-Capture Reactions of Ester Carbanions with Bis(imidoyl)chlorides of Oxalic Acid
作者:Peter Langer、Jörg Wuckelt、Manfred Döring
DOI:10.1021/jo991377u
日期:2000.2.1
A variety of pyrrolo[3,2-b]pyrrole-2,5-diones were efficiently prepared by a new domino-reaction of ester carbanions with oxalic acid−bis(imidoyl)chlorides. This reaction proceeded by condensation of 2 equiv of the ester with the bis(imidoyl)chloride and subsequent intramolecular attack of the nitrogen atoms of the bis-enamine intermediate onto the ester groups. The products, which can be regarded
通过酯碳负离子与草酸-双(亚氨基)氯化物的新型多米诺反应有效地制备了多种吡咯并[3,2-b]吡咯-2,5-二酮。该反应通过2当量酯与双(亚氨基)氯化物的缩合和随后双烯胺中间体的氮原子对酯基团的分子内攻击而进行。该产品可被视为戊烯的双内酰胺,由于其光学特性、稳定性和低溶解度,是有用的合成颜料。吡咯并[3,2-b]吡咯-2,5-二酮的UV-vis性质可以通过连接到杂环核上的取代基来有效控制。研究了新环化反应的范围和局限性。