- IBX-Promoted Oxidative Cyclization of N-Hydroxyalkyl Enamines: A Metal-Free Approach toward 2,3-Disubstituted Pyrroles and Pyridines
-
An iodoxybenzoic acid-mediated selected oxidative cyclization of N-hydroxyalkyl enamines was developed. Through this strategy, a variety of 2,3-disubstituted pyrroles and pyridines were produced in good selectivity involving oxidation of alcohol, followed by condensation of aldehyde and α-C of enamines. Furthermore, this metal-free method has several advantages, including the use of environmentally friendly reagents, broad substrate scope, mild reaction conditions, and high efficiency.
- Gao, Peng,Chen, Huai-Juan,Bai, Zi-Jing,Zhao, Mi-Na,Yang, Desuo,Wang, Juan,Wang, Ning,Du, Lele,Guan, Zheng-Hui
-
p. 7939 - 7951
(2020/07/16)
-
- Visible-light-induced formal [3+2] cycloaddition for pyrrole synthesis under metal-free conditions
-
A photocatalytic formal [3+2] cycloaddition of 2H-azirines with alkynes has been achieved under irradiation by visible light in the presence of organic dye photocatalysts. This transformation provides efficient access to highly functionalized pyrroles in good yields and has been applied to the synthesis of drug analogues. A primary trial of photocascade catalysis merging energy transfer and redox neutral reactions was shown to be successful. Photo(chemistry) op: A photocatalytic formal [3+2] cycloaddition of 2H-azirines with alkynes has been established under the irradiation of visible light in the presence of an organic dye. This transformation provides efficient access to highly functionalized pyrroles in good yields and has been applied to the formal synthesis of an inhibitor for HMG-CoA reductase.
- Xuan, Jun,Xia, Xu-Dong,Zeng, Ting-Ting,Feng, Zhu-Jia,Chen, Jia-Rong,Lu, Liang-Qiu,Xiao, Wen-Jing
-
p. 5653 - 5656
(2014/06/10)
-
- METHOD FOR PREPARING 2H-AZIRINE CARBOXYLIC ESTERS
-
The invention relates to a method for preparing 2H-azirine carboxylic esters. More specifically, the invention relates to a method for preparing 2H-azirine carboxylic esters starting from α-diazo-β-keto oxime ethers in the presence of a rhodium (II)-based
- -
-
Paragraph 00128, 00131; 0066
(2013/06/27)
-
- Expedient synthesis of highly substituted pyrroles via tandem rearrangement of α-diazo oxime ethers
-
An efficient rhodium-catalyzed synthesis of 2H-azirines and pyrroles has been developed. Novel rearrangement of α-oximino ketenes derived from α-diazo oxime ethers provides 2H-azirines bearing quaternary centers and allows for subsequent rearrangement to highly substituted pyrroles in excellent yields.
- Jiang, Yaojia,Chan, Wei Chuen,Park, Cheol-Min
-
supporting information; experimental part
p. 4104 - 4107
(2012/04/10)
-
- Studies on cycloaddition reactions of 1,3-diphenyl-2-azaallyl lithium and ethyl (benzylideneamino) acetate anion with α-oxoketene dithioacetals
-
The α-oxoketene dithioacetals undergo anionic [1,3] cycloaddition with 1,3-diphenyl-2-azaallyllithium to give either pyrroles or spiropyrrolines with two exceptions. Lithium bromide/triethylamine induced cycloaddition of ethyl (benzylideneamino)acetate (7
- Balu, Maliakel P.,Ila, Hiriyakkanavar,Junjappa, Hiriyakkanavar
-
p. 6771 - 6782
(2007/10/02)
-
- Organische Synthesen mit Uebergangsmetall-Komplexen XLV. 3-Hydroxypyridine, 1H-Pyrrole und 2-Hydroxypyrrol-Derivate aus einem Aminocarben-Chromkomplex und Alkinen
-
Pyrroles VI, 3-hydroxypyridines V and 2-hydroxypyrroles IX have been obtained from (amino,phenylcarbene)pentacarbonyl-chromium (I) by simple two-step procedures.The first step involves the generation of 2-azaallenyl(pentacarbonyl)chromium complexes III, and VIII by condensation of I with an aldehyde II and an acid chloride VII, respectively.Complexes III react with alkynes IVa-i to give pyrroles VI and 3-hydroxypyridines V.VIII adds alkynes IVa,e,g to give 2-hydroxypyrroles IX.
- Aumann, Rudolf,Heinen, Heinrich
-
-