A New Synthesis of Push-Pull Pyrroles, Their Oxidation to Stable 3<i>H</i>-Pyrroles and an Unexpected Anellation Reaction
作者:Gunther Buehrdel、Rainer Beckert、Petra Herzigova、Eva Petrlikova、Dirk Schuch、Eckhard Birckner、Helmar Goerls
DOI:10.1002/ejoc.200900295
日期:2009.7
A new synthesis of push-pull pyrroles of type 5 was developed starting from bis(imidoyl chlorides) 1 and various iminodiacetic acid derivatives 3. The use of appropriate N-trifluoroacetyl residues as protecting/activating group proved to be the method of choice for the straightforward preparation of the 3,4-diarylamino-1H-pyrroles 5. When benzothiazole substructures are present in 2,5-position of heterocycles
从双(亚氨基酰氯)1 和各种亚氨基二乙酸衍生物 3 开始,开发了 5 型推挽吡咯的新合成方法。使用适当的 N-三氟乙酰基残基作为保护/活化基团被证明是3,4-二芳基氨基-1H-吡咯的直接制备 5. 当苯并噻唑亚结构存在于杂环 5 的 2,5-位时,双电子氧化以优异的产率生成 6 型 3H-吡咯。然而,在氰基或酯基团的情况下,进一步的氧化过程立即通过分子内环烷化作用产生新的 3H-吡咯并 [3,4-b] 喹喔啉 7。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)