Article
Chemistry, Organic
Giacomo Mari, Matteo Corrieri, Lucia De Crescentini, Gianfranco Favi, Stefania Santeusanio, Fabio Mantellini
Summary: Substituted 1-aminopyrroles can be easily accessed through an iron-catalyzed cascade reaction of 1,2-diaza-1,3-dienes, which involves a [4+2] cyclodimerization and ring contraction process. The presence of activated hydrogen in the terminal position of the azo-enic moiety is crucial for the synthesis of pyrroles.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Arup Jyoti Das, Sajal Kumar Das
Summary: A base-mediated [4+2] annulation reaction between indole-2-carboxamides and 2,3-epoxytosylates has been developed, affording 3-substituted pyrazino[1,2-a]indol-1-ones in high yields with high diastereoselectivity. Notably, this one-pot process is chemo- and regioselective towards both starting materials, and does not generate 4-substituted pyrazino[1,2-a]indol-1-ones or tetrahydro-1H-[1,4]diazepino[1,2-a]indol-1-ones, regardless of the substituent on the distal epoxide C3 or its cis/trans configuration. To the best of our knowledge, this represents the first successful example of the one-pot annulation of indole-based diheteronucleophiles with epoxide-based dielectrophiles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Deyu Wu, Zhengqiang Liu, Yiting Chang, Jiajing Chen, Haixiang Qi, Yi Dong, Heng Xu
Summary: A synthetic protocol for the Cp*Co-III-catalyzed C-H amidation/annulation of 2-aryl-1H-imidazoles with 1,4,2-dioxazol-5-ones has been developed, affording imidazo[1,2-c]quinazoline derivatives with broad substrate scope and moderate to good yields. This method shows promising applications in the synthesis of imidazo[1,2-c]quinazoline drugs.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Organic
Hongchao Yin, Yuan Tian, Chenxi Guo, Ran Song, Daoshan Yang, Jian Lv
Summary: A facile tandem oxa-Nazarov cyclization and dibromination has been developed, in which the combination of Cu(OTf)2 and diphenyl phosphate (DPP-H) synergistically promotes the coupling of conjugated 1,2-diketones and N-bromosuccinimide, leading to the formation of 2,4-dibromo-3(2H)-furanones in good yields.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Jiangjie Zhang, Jun Ying, Xiao-Feng Wu
Summary: A novel palladium-catalyzed tandem cyclization and carbonylation reaction was developed for the synthesis of indeno[1,2-b]indol-10(5H)-one derivatives. The reaction proceeded smoothly with high yields using formic acid as the CO source. This method can also be applied for the modification of various bioactive molecules.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Wei Huang, Jiahui Bai, Yinlong Guo, Qinglei Chong, Fanke Meng
Summary: A catalytic enantioselective coupling of 1,1-disubstituted allenes and aldehydes is achieved through regiodivergent oxidative cyclization followed by stereoselective protonation or reductive elimination promoted by chiral phosphine-Co complexes. This unprecedented reaction pathway for Co catalysis allows for the catalytic enantioselective generation of metallacycles with divergent regioselectivity accurately controlled by chiral ligands, leading to a wide range of allylic alcohols and homoallylic alcohols in high yields and excellent regioselectivity, diastereoselectivity, and enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Soumen Pandit, Vinay Kumar Pandey, Amit Singh Adhikari, Suresh Kumar, Arvind Kumar Maurya, Ruchir Kant, Nilanjana Majumdar
Summary: An efficient method for the construction of hydrocarbazoles bearing three continuous sterically hindered stereocenters has been developed using a diastereoselective palladium-catalyzed [4 + 2]-cycloaddition/dearomatization reaction. The reaction occurs at ambient conditions with the formation of a 1,4-zwitterionic intermediate from gamma-methylidene-delta-valerolactones. The synthetic utility of this method is demonstrated by the various transformations possible from the products, and the catalytic asymmetric aspect has also been explored.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Soumen Pandit, Vinay Kumar Pandey, Amit Singh Adhikari, Suresh Kumar, Arvind Kumar Maurya, Ruchir Kant, Nilanjana Majumdar
Summary: An efficient method has been developed for the construction of hydrocarbazoles bearing three continuous sterically hindered stereocenters via a highly diastereoselective palladium-catalyzed [4 + 2]-cycloaddition/ dearomatization of 3-nitroindoles. The multifaceted transformations of the products demonstrate the further synthetic utility of this method. The catalytic asymmetric aspect of this transformation has also been explored.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Shengkun Guo, Xiaoyu Shen, Xiaoyun Chen, Huaguang Yu, Ying Han, Chaoguo Yan, Yaocheng Shi, Hong Hou, Shaoqun Zhu
Summary: This study presents a photoinduced copper-catalyzed 1,2-difunctionalization of 1,3-dienes. The generation of selenium atom radicals through visible light irradiation of diselenides leads to radical addition with 1,3-dienes, resulting in the formation of allyl radical intermediates. Rapid Z/E isomerization enables thermodynamically favorable intermediate formation, facilitating copper-catalyzed stereoselective functionalization with different nucleophiles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Ahmed El Akkaoui, Jamal Koubachi, Gerald Guillaumet, Said El Kazzouli
Summary: This review surveys recent developments in organometallic-chemistry-based methods for preparing and functionalizing imidazo[1,2-b]pyridazines, highlighting advances in C-H activation, N-arylation, and sequential couplings for these heterocyclic systems. This review does not include procedures involving metal-based catalysis.
Article
Chemistry, Organic
Ladislav Loska, Vojtech Docekal, Ivana Cisarova, Jan Vesely
Summary: The study presents an asymmetric NHC-catalyzed formal [4 + 2] cycloaddition of heterocyclic alkenes with an azolium-dienolate intermediate. The reaction is achieved without external oxidation of the Breslow intermediate. Good yields (typically about 90%) and stereochemical outcomes (in most cases, dr > 20/1, and ee = 70-99%) were obtained for heterocyclic cyclohexenones. The synthetic utility of the protocol was demonstrated by the scope of heterocyclic alkenes.
Article
Chemistry, Organic
Mina Hariri, Fatemeh Darvish, Karen-Pacelye Mengue Me Ndong, Nora Sechet, Geraud Chacktas, Hooriye Boosaliki, Minh Loan Tran Do, Gabin Mwande-Maguene, Jacques Lebibi, Alexander R. Burilov, Tahar Ayad, David Virieux, Jean-Luc Pirat
Summary: This study presents a straightforward synthesis of phosphorus-based heterocycles, 2-phenyl 1H-isophosphinoline 2-oxides 1, using a gold(I) catalyzed reaction with electron-poor alkynes. The reaction, conducted under microwave activation with PPh3AuCl precatalyst and triflic acid, resulted in moderate to quantitative yields of isophosphinoline 2-oxides 1 through a regioselective 6-endo-dig hydroarylation cyclization, demonstrating a promising approach for the synthesis of phosphorus heterocycles.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yanmin Guo, Rong Chang, Zhen Fu, Cong-Ying Zhou, Zhen Guo
Summary: This study presents a visible-light-induced dehydrogenative [4+2] annulation of benzothioamides and alkynes using the metal-free heterogeneous photocatalyst graphitic carbon nitride (g-C3N4). The reaction proceeds smoothly under mild aerobic conditions and gives a variety of isothiochromenes in good yields. Detailed mechanistic studies reveal that g-C3N4 promotes the formation of a sulfur-centered radical under visible-light irradiation through a single electron transfer process.
Article
Chemistry, Organic
Yueyue Zhu, Rupeng Dai, Chaoqun Huang, Wang Zhou, Xiaoyuan Zhang, Kundi Yang, Hongmei Wen, Wei Li, Jian Liu
Summary: In this study, a novel and efficient synthetic method was developed to construct isoquinolone scaffold and other valuable derivatives through catalytic reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Yang'en You, Shaozhong Ge
Summary: An enantioselective cobalt-catalyzed hydrosilylation/cyclization reaction of 1,6-enynes with secondary and tertiary hydrosilanes produced chiral organosilane products in high yields and excellent enantioselectivity, which could be further converted into a variety of chiral five-membered heterocyclic compounds without loss of enantiopurity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
