α-Hydroxy acid as an aldehyde surrogate: metal-free synthesis of pyrrolo[1,2-<i>a</i>]quinoxalines, quinazolinones, and other N-heterocycles <i>via</i> decarboxylative oxidative annulation reaction
and efficient procedure for the synthesis of pyrrolo[1,2-a]quinoxalines, quinazolinones, and indolo[1,2-a]quinoxaline has been developed. The key features of our method include the in situ generation of aldehyde from α-hydroxy acid in the presence of TBHP (tert-butyl hydrogen peroxide), and further condensation with various amines, followed by intramolecular cyclization and subsequent oxidation to afford
开发了一种无金属且有效的合成吡咯并[1,2- a ]喹喔啉、喹唑啉酮和吲哚[1,2- a ]喹喔啉的方法。该方法的主要特点包括在 TBHP(叔丁基过氧化氢)存在下,由 α-羟基酸原位生成醛,并与各种胺进一步缩合,然后进行分子内环化和随后的氧化,得到相应的喹喔啉、喹唑啉酮衍生物,产率中等至高。
One-Pot Synthesis of Pyrrolo[1,2-<i>a</i>]quinoxaline Derivatives via Iron-Promoted Aryl Nitro Reduction and Aerobic Oxidation of Alcohols
作者:Maria de Fatima Pereira、Valérie Thiéry
DOI:10.1021/ol302006b
日期:2012.9.21
describe a new one-pot method to synthesize 4,7-substituted pyrrolo[1,2-a]quinoxalines and related heterocyles through a cascade of redox reactions/imine formation/intramolecular cyclization. This procedure tolerates readily available substituted 1-(2-nitrophenyl)pyrrole derivatives and aliphatic or benzylic alcohols as starting materials using iron powder and acidic conditions. This is the first example
在这里,我们描述了一种新的一锅法,通过级联的氧化还原反应/亚胺形成/分子内环化反应来合成4,7-取代的吡咯并[1,2- a ]喹喔啉和相关杂环。该方法耐受使用铁粉和酸性条件容易获得的取代的1-(2-硝基苯基)吡咯衍生物和脂族或苄基醇作为起始原料。这是在一个罐中通过铁介导的芳基硝基还原和酒精的好氧氧化构造N-杂环的第一个例子。
Molybdenum-Catalyzed Synthesis of Nitrogenated Polyheterocycles from Nitroarenes and Glycols with Reuse of Waste Reduction Byproduct
作者:Rubén Rubio-Presa、Marı́a R. Pedrosa、Manuel A. Fernández-Rodríguez、Francisco J. Arnáiz、Roberto Sanz
DOI:10.1021/acs.orglett.7b02792
日期:2017.10.6
the efficient synthesis of pyrrolo(indolo)[1,2-a]quinoxalines and pyrrolo(indolo)[3,2-c]-quinolines from readily available nitrobenzenes and glycols is reported. The process utilizes the carbonyl byproduct of the initial dioxomolybdenum(VI)-catalyzed reduction of nitroaromatics with glycols as a reagent for the imine generation. This method represents the first sustainable domino reaction for the preparation