15345-47-8Relevant academic research and scientific papers
Cross-conjugated oligomers from pyrrole, benzene and carbonyl building blocks
Hormaza, Angelina,Hinneschiedt, Sabine,Meier, Herbert
, p. 229 - 233 (2004)
Chalcones can serve as C2 or C3 components for the formation of 1H-pyrroles. In particular the reaction with tosylisocyanid could be applied to the oligochalcones 2d-g with up to 6 enone units. A series of cross-conjugated oligomers 8d-g was obtained; these compounds consist of a chain of 1,4-phenylene, carbonyl and 1H-pyrrole-3,4-diyl building blocks. The benzene rings bear two propoxy sidechains in order to enhance the solubility.
Microwave mediated facile one-pot synthesis of polyarylpyrroles from but-2-ene- and but-2-yne-1,4-diones
Rao, H. Surya Prakash,Jothilingam,Scheeren, Hans W.
, p. 1625 - 1630 (2004)
Several pyrrole derivates with multiple aryl substituents were prepared conveniently in a one pot-reaction from but-2-ene-1,4-diones and but-2-yne-1,4-diones via hydrogenation of the carbon-carbon double bond/triple bond followed by amination-cyclization. The reaction could be performed with ammonium formate or alkyl/arylammonium formates under Pd/C in polyethylene glycol-200 (PEG-200) under microwave irradiation. Using this procedure, different aryl-substituted pyrroles were prepared. Furthermore, studies on microwave vs thermal conditions indicate faster heating under microwave conditions was responsible for rate enhancement.
An efficient synthesis of substituted pyrroles with the aid of a low-valent titanium reagent
Shi, Daqing,Shi, Chuling,Wang, Xiangshan,Zhuang, Qiya,Tu, Shujiang,Hu, Hongwen
, p. 2239 - 2241 (2004)
A short and efficient synthesis of substituted pyrroles was accomplished in good yields via the novel coupling cyclization reaction of 1,3-diketones with imines or oximes promoted by TiCl4/ Zn system.
Photoredox-Enabled Chromium-Catalyzed Alkene Diacylations
Liu, Jing,Lu, Liang-Qiu,Luo, Yixin,Zhao, Wei,Sun, Peng-Chao,Jin, Weiwei,Qi, Xiaotian,Cheng, Ying,Xiao, Wen-Jing
, p. 1879 - 1885 (2022/02/07)
Transition-metal-catalyzed cross-coupling reactions are a powerful tool to construct carbon-carbon bonds in modern synthetic chemistry. Chromium catalysis is much less developed compared with the widely used palladium and nickel catalysis. Herein, we repo
A convenient approach for the synthesis of substituted pyrroles by using phosphoric acid as a catalyst and their photophysical properties
Ai, Liankun,Ibrahim, Yusuf Ajibola,Li, Baolin,Li, Jiahui
, (2021/12/21)
Twenty-three new pyrrole compounds aside from six knowns, including the synthetically challenging tetra- and penta-substituted pyrroles from the corresponding 1,4-dicarbonyl through Paal-Knorr synthesis in the presence of 5% phosphoric acid as the catalyst. Our method is noteworthy for cheap catalyst, uncomplicated experimental setup under air atmosphere, scalability, and excellent yields. The fluorescence of some selected pyrroles was investigated in dilute solution, and we found that all novel pyrroles emit strong blue fluorescences with considerable Stokes shifts.
Acyl radicals from α-keto acids using a carbonyl photocatalyst: Photoredox-catalyzed synthesis of ketones
Zhu, Da-Liang,Wu, Qi,Young, David James,Wang, Hao,Ren, Zhi-Gang,Li, Hong-Xi
, p. 6832 - 6837 (2020/10/12)
Acyl radicals have been generated from α-keto acids using inexpensive and commercially available 2-chloro-thioxanthen-9-one as the photoredox catalyst under visible light illumination. These reactive species added to olefins or coupled with aryl halides via a bipyridylstabilized Ni(II) catalyst, enabling easy access to a diverse range of ketones. This reliable, atom-economical, and eco-friendly protocol is compatible with a wide range of functional groups.
Visible-Light-Promoted Photocatalyst-Free Hydroacylation and Diacylation of Alkenes Tuned by NiCl2·DME
Zhao, Xinxin,Li, Bing,Xia, Wujiong
, p. 1056 - 1061 (2020/02/15)
Herein, we describe a visible light-promoted hydroacylation strategy that facilitates the preparation of ketones from alkenes and 4-acyl-1,4-dihydropyridines via an acyl radical addition and hydrogen atom transfer pathway under photocatalyst-free conditions. The efficiency was highlighted by wide substrate scope, good to high yields, successful scale-up experiments, and expedient preparation of highly functionalized ketone derivatives. In addition, this protocol allows for the synthesis of 1,4-dicarbonyl compounds through alkene diacylation in the presence of NiCl2·DME.
Highly Regioselective Synthesis of Multisubstituted Pyrroles via Ag-Catalyzed [4+1C]insert Cascade
He, Kun,Jin, Yi,Lin, Jun,Luo, Kaixiu,Mao, Shuai,Pan, Junhong,Shao, Zhihui,Yu, Xianglin
, p. 3733 - 3740 (2020/04/15)
An efficient [4+1C]insert approach to the coupling of enaminones with donor/acceptor or donor/donor carbenes by the AgOTf-catalyzed C-C bond carbenoid formal insertion/cyclization/[1,5]-shift cascade reaction was successfully developed, providi
Synthesis of Tetrasubstituted Pyrroles from Homopropargylic Amines via a Sonogashira Coupling/Intramolecular Hydroamination/Oxidation Sequence
Wang, Chan,Huang, Kaimeng,Wang, Junying,Wang, Hongkai,Liu, Lingyan,Chang, Weixing,Li, Jing
, p. 2795 - 2802 (2015/09/28)
A one-pot reaction of homopropargylic amines and aryl iodides was developed in the presence of a palladium (Pd) catalyst and generated a series of tetrasubstituted pyrrole derivatives in good to high yields. This process involved a Sonogashira, intramolecular hydroamination, cyclization and oxidation sequence of reactions.
Synthesis of tetrasubstituted pyrroles from terminal alkynes and imines
Hu, Yancheng,Wang, Chunxiang,Wang, Dongping,Wu, Fan,Wan, Boshun
supporting information, p. 3146 - 3149 (2013/07/26)
Tetrasubstituted pyrroles can be obtained via the reaction of terminal alkynes and imines using nBuLi as the base in one step with high chemoselectivity (method 1). Alternatively, the intermediate propargylamines can also react with imines to afford tetrasubstituted pyrroles when using LiHMDS as the base (method 2), which provides a complementary method to construct the pyrroles with different substituents.
