Article
Chemistry, Organic
Chengkai Luo, Mingzhong Cai, Ruonan Zhao, Bin Huang
Summary: An efficient heterogeneous copper(I)-catalyzed three-component tandem cyclization reaction has been developed using 3-(2-aminoethylamino)propyl-modified MCM-41-bound copper(I) bromide as the catalyst. The reaction proceeded smoothly in DMSO at 120 degrees C and delivered polysubstituted pyridines in good to high yields. The catalyst can be easily prepared from commercially available and inexpensive reagents and reused multiple times without loss of catalytic efficiency.
SYNTHETIC COMMUNICATIONS
(2023)
Article
Chemistry, Applied
Dirgha Raj Joshi, Ikyon Kim
Summary: The study successfully achieved multi-functionalization of the pyridine motif in indolizine through [5+1] annulative construction, introducing three different functional groups at the C5, C6, and C7 positions. The solvent (2-MeTHF) and the hydroxyl of 2-hydroxyacetophenones were found to play crucial roles in the successful cyclization event. Furthermore, the elaboration of the resulting scaffold and the potential expansion using other methyl ketones were also demonstrated.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Applied
Wenbo Hu, Liqin Yan, Youpeng Zuo, Shuwen Kong, Yue Pu, Qiang Tang, Xinyu Wang, Xinwei He, Yongjia Shang
Summary: A cascade C-H activation, annulation, and etherification reaction has been developed for the flexible synthesis of N-alkoxylated 3-arylisoindolin-1-ones. This method generates three new bonds (C-C, C-N, and C-O) to afford a series of tetrasubstituted isoindolin-1-ones with yields ranging from 49% to 82%. The utility of this method has been demonstrated through gram-scale synthesis and synthetic transformations to access structurally diverse isoindolinones.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Physical
Sidi Cheng, Yu Luo, Ting Yu, Jing Li, Chunfang Gan, Shuang Luo, Qiang Zhu
Summary: An unactivated alkene was successfully subjected to 1,2-difunctionalization through a palladium-catalyzed four-component cascade reaction, leading to the convenient synthesis of acetamides with various substituents and pyrrolo-fused heterocycles.
Article
Chemistry, Organic
Jonathan Bajohr, Matthias D. Boehme, Jiacheng Gao, F. Ekkehardt Hahn, Mark Lautens
Summary: The diastereoselective synthesis of sulfonylated indolines has been reported. Reactive benzylic sulfinates are generated through a palladium-catalyzed dearomative sulfination of (aza)indole-tethered aryl iodides. These intermediates react with electrophiles in a one-pot, two-step process to give sulfonylated products with good yields and excellent diastereoselectivity. This scalable three-component sequence can also be used for the synthesis of sulfonamides. Furthermore, further derivatizations of aryl iodide containing products lead to the formation of spiro- and alkynylated indoline products.
Article
Chemistry, Organic
Lvyin Zheng, Gongping Liu, Xiaoying Zou, Yumei Zhong, Lei Deng, Yingying Wu, Beining Yang, Yihan Wang, Wei Guo
Summary: The metal-free [2+2+1] three-component cascade annulations described in this study allow for the efficient synthesis of multiply substituted 3-cyano-thiophenes with good functional group tolerance and simple reaction conditions, showing potential applications in medicinal chemistry through late-stage modifications of structurally complex bioactive molecules and drugs.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Kai Wei, Yu-Cui Sun, Rui Li, Jing-Feng Zhao, Wen Chen, Hongbin Zhang
Summary: A new synthesis process for highly functionalized pyridines has been reported, utilizing a tandem reaction sequence. This method provides good yields of pyridines with accessible starting materials and shows potential for modifying frameworks of BINOL and natural products.
Article
Chemistry, Multidisciplinary
Zhengtian Ding, Yiming Wang, Wenfeng Liu, Yate Chen, Wangqing Kong
Summary: The study presents an unprecedented nickel-catalyzed one-pot synthesis of enantioenriched spiroindanones from readily available 1,6-enynes and o-formylarylboronic acids. The reaction proceeds smoothly under redox-neutral conditions, demonstrating excellent regio-, enantio-, and diastereoselectivity with a broad substrate scope.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Luyao Wang, Mengting Li, Zhitao Ning, Xi Zhang, Ying Fu, Zhengyin Du
Summary: An efficient visible-light-assisted, copper-catalyzed tandem radical cyclization of N-propargylindoles with cyclic ethers has been established. A series of 2-oxoalkyl-9H-pyrrolo[1,2-a]indol-9-ones with potential biological activities were synthesized in moderate yields using a dual catalytic system with copper acetate as a transition metal catalyst and eosin Y as a visible light catalyst.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Zhao-Ying Yang, Heng Luo, Ming Zhang, Xiao-Chen Wang
Summary: A novel method for the catalyzed hydroboration/hydrogenation cascade reduction of pyridines has been developed, particularly effective for 2,3-disubstituted pyridines, yielding piperidines with high cis selectivity. Mechanistic studies showed that the pyridine substrates and piperidine products acted as bases in cooperation with B(C6F5)(3) to split H-2. This method demonstrated broad functional group tolerance and applicability for the synthesis of biologically active molecules.
Article
Chemistry, Organic
Kovuru Gopalaiah, Renu Choudhary
Summary: An efficient protocol for the synthesis of symmetrical and unsymmetrical 2,4,6-trisubstituted pyridines has been developed using iron(II) triflate as a catalyst and molecular oxygen as an oxidant. The reaction proceeds smoothly with a broad substrate scope, undergoing oxidative condensation followed by double alkynylation and amination processes.
Article
Chemistry, Physical
Xing-Yu Wang, Xiao-Bing Wang, Yin Tian, Cheng Peng, Ming-Sheng Xie, Hai-Ming Guo
Summary: A highly enantioselective dearomative [3 + 2] annulation reaction was achieved using quinolines, isoquinolines, and pyridines with donor-acceptor aminocyclopropanes. By utilizing a C-1-symmetric imidazoline-pyrroloimidazolone pyridine as the tridentate ligand and Co(OTf)2 as the Lewis acid, chiral indolizidine and benzo-fused indolizidine derivatives were obtained with good yields (up to 98%), excellent diastereoselectivities (>20:1 dr), and excellent enantioselectivities (up to 98% ee). Mechanistic experiments and DFT calculations revealed that the tridentate nitrogen ligand acted as a bifunctional chiral ligand, coordinating with the Co(II) salt and forming a H-bond to facilitate the nucleophilic attack of N-heteroaromatics and achieve high enantioselectivity.
Article
Chemistry, Inorganic & Nuclear
Nagaraju Kerru, Lalitha Gummidi, Suresh Maddila, Sreekantha B. Jonnalagadda
Summary: The study presents the preparation and characterization of magnesium loaded hydroxyapatite composite, and evaluates its catalytic activity for the synthesis of novel dihydropyrazolo[3,4-b] pyridine derivatives. The composite showed excellent yields, reusability, and simplicity in operation, making it a promising catalyst for organic synthesis.
INORGANIC CHEMISTRY COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Xiao-Xia Ming, Shuai Wu, Ze-Yu Tian, Jia-Wei Song, Cheng-Pan Zhang
Summary: The study confirmed the potential of (2-bromoethyl)diphenylsulfonium triflate as a powerful vinylation reagent in Sonogashira cross-coupling reactions. The vinylation proceeded smoothly at 25 degrees C under Pd/Cu catalysis, yielding a variety of 1- and 2-unsubstituted 1,3-enynes in moderate to excellent yields. This protocol represents the first application of (2-haloethyl)diphenylsulfonium triflate as a CH=CH2 transfer source in organic synthesis.
Article
Chemistry, Organic
Shravani Battula, Hemalatha Bukya, Kunta Chandra Shekar, Kiranmai Nayani
Summary: A Rh(III)-catalyzed annulation was achieved between 2-arylimidazo[1,2-a]pyridines and p-quinols, leading to the formation of bridged heterocycles with three contiguous stereocenters via a twofold conjugate addition. The cascade reaction showed diastereoselectivity and proceeded through a sequential Rh-catalyzed ortho C(sp(2))-H functionalization of the aryl group of imidazo[1,2-a]pyridine with p-quinol, followed by an intramolecular conjugate addition, to produce a series of diverse and novel bridged heterocycles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
