Article
Chemistry, Organic
Shaocong Shen, Zhijian Zong, Nan Sun, Baoxiang Hu, Zhenlu Shen, Xinquan Hu, Liqun Jin
Summary: A well-defined geometry-constrained tridentate NNN-cobalt complex was developed for regio- and stereoselective hydrosilylation of 1,3-diynes, tolerating a wide range of symmetrical and unsymmetrical substrates. The scale-up reaction demonstrated the practicality and efficiency of the developed strategy for the synthesis of diverse 1,3-enynylsilanes.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Physical
Bing Zhang, Xueying Guo, Lei Tao, Ruolin Li, Zhenyang Lin, Wanxiang Zhao
Summary: The deoxygenative reduction of 1,3-diketones using a rhodium-catalyzed method exhibits high regioselectivity toward aliphatic carbonyl reduction, good functional group tolerance, and potential in the late-stage modification and synthesis of natural products and pharmaceutical skeletons. Preliminary mechanistic studies suggest a lower energy barrier for aliphatic C = O insertion, explaining the high regioselectivity observed in this reduction.
Article
Chemistry, Multidisciplinary
Mu-Jia Luo, Gui-Fen Lv, Jing-Hao Qin, Chong-Hui Xu, Yang Li, Jin-Heng Li
Summary: This study presents a rhodium-catalyzed electrochemical reaction for the selective synthesis of structurally diverse hexasubstituted arenes. The method demonstrates excellent selectivity and high atom economy.
Article
Chemistry, Multidisciplinary
Mu-Jia Luo, Gui-Fen Lv, Jing-Hao Qin, Chong-Hui Xu, Yang Li, Jin-Heng Li
Summary: A cooperative rhodium-catalyzed electrochemical 1,3-butadiyne [2 + 2 + 2] cyclotrimerization is presented, which selectively produces hexasubstituted arenes. The method features high selectivity, good functional group tolerance, and high atom economy.
Article
Chemistry, Multidisciplinary
Surajit Panda, Amareshwar Nanda, Rakesh R. Behera, Rahul Ghosh, Bidraha Bagh
Summary: Commercially available Co-2(CO)(8) is an effective catalyst for the hydrosilylation of nitroarenes under thermal and photochemical conditions. This protocol selectively reduces a wide variety of nitroarenes with different functionalities to aromatic amines, expanding its potential utility in drug synthesis. Experimental evidence supports a radical pathway for this reaction.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Kailun Liang, Lijun Lu, Xing Liu, Dali Yang, Shengchun Wang, Yiming Gao, Hesham Alhumade, Hong Yi, Aiwen Lei
Summary: In this study, a facile and efficient cobalt-catalyzed cyclotrimerization of alkynes was disclosed using electrochemical tools. Both terminal and internal alkynes were tolerated under mild reaction conditions, producing products with high regioselectivity. The valence of Co species was accurately tuned through electrochemical redox to cycle the catalyst smoothly during the entire reaction process.
Article
Chemistry, Organic
Jakub Szyling, Aleksandra Szymanska, Adrian Franczyk, Jedrzej Walkowiak
Summary: A simple, efficient, and selective method for the preparation of boryl-functionalized enynes or dienes via catalytic diboration has been developed. The method was proven to be effective and was applied in advanced organic transformations.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jinjin Yang, Deping Kong, Hongli Wu, Zhen Shen, Hongyan Zou, Wentao Zhao, Genping Huang
Summary: In this study, the detailed reaction mechanism and selectivity origins of the palladium-catalyzed double-alkoxycarbonylation of 1,3-diynes were elucidated using density functional theory calculations. The computations revealed that the reaction proceeds via two consecutive catalytic cycles with the same mechanism, and the hydropalladation step determines the rate and regioselectivity of the reaction.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Sanxia Chen, Wenxuan Xue, Conghui Tang
Summary: An easily prepared core-shell heterogeneous nanocobalt catalyst was developed for the selective reduction of N-heteroarenes under mild conditions and ambient atmosphere. The catalyst showed high selectivity and efficiency in hydrogenating various derivatives. It also demonstrated good tolerance towards substrates with sensitive functional groups, and could be applied in liquid organic hydrogen storage system.
Article
Polymer Science
Nana Kikuta, Takahiro Shindo, Yu-ki Sugiyama, Takeshi Yamada, Sentaro Okamoto
Summary: The novel synthetic method for hyperbranched polymers utilizes a cobalt catalyst to promote the successful polymerization of aromatic diynes with internal alkynes, resulting in soluble polymers without the production of insoluble materials. The resulting polymer's molecular weight and degree of branching can be controlled by selecting the internal alkyne monomer and adjusting its loading amount.
Article
Chemistry, Organic
Han Gao, Wujie Wang, Xiangying Lv, Gang Lu, Yuliang Li
Summary: The mechanism of Co(iii)-catalyzed annulation of N-chlorobenzamide with styrene was computationally studied, focusing on the effects of chiral cyclopentadienyl (Cp) ligands on enantioselectivity using energy decomposition analysis (EDA). The study revealed a spin-crossover event of Co complexes in the computed energy profile, with the triplet state of Co species being favored in most intermediates and transition states. The irreversible styrene migratory insertion was identified as the enantioselectivity-determining step, with steric effects being the dominant factor for high-level enantiocontrol, emphasizing the importance of additional bulky substituents on the Cp ring of trisubstituted BINOL-Cp ligands.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Shoucheng Dong, Zhenfeng Tian, Junda Wang, Lin He, Jie Li
Summary: Salt-stabilized organozinc pivalates with OPiv-coordination exhibit significant counterion-effect, enabling an efficient cobalt-catalyzed 1,4-carbosulfonylation of 1,3-enynes with sulfonyl chlorides under mild conditions. Both aryl and alkyl zinc pivalates show higher reactivity compared to traditional halide-supported organozinc reagents, providing a convenient access to highly functionalized a-allenyl sulfones through cascade C-C/C-S bond formation. Additionally, late-stage modifications of drug-like compounds and facile transformations of the resulting allenes demonstrate the synthetic utility of this protocol.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Organic
Patricia S. M. Amado, Luis M. T. Frija, Jaime A. S. Coelho, Paul M. O'Neill, Maria L. S. Cristiano
Summary: A novel protocol for the synthesis of nonsymmetrical 1,2,4,5-tetraoxanes and 1,2,4-trioxanes using heterogeneous silica sulfuric acid (SSA) catalyst has been reported. The method involves different ketones reacting under mild conditions to generate corresponding endoperoxides in good yields, with the assistance of molecular orbital calculations. This approach provides a valid alternative for the synthesis of new biologically active endoperoxides using readily available and inexpensive reagents with recyclable properties.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Murugan Krishnan, Murugavel Kathiresan, Chandrasekar Praveen
Summary: In this study, we disclose the oxidative homocoupling of terminal alkynes under electrochemically generated Cu(I) catalysis and establish the scope of this method. This method has several advantages, such as good synthetic yields, functional group tolerance, oxidant-free conditions, and no cross-selectivity. The study also reveals that the product ratio is dependent on the electronic nature of the alkynyl substituents.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Physical
Decai Ding, Linchuan Zhang, Hao Wen, Chuan Wang
Summary: Here, a cobalt-catalyzed asymmetric reductive 1,2-dicarbofunctionalization of 1,3-dienes using obromoaryl imines as a bis-electrophilic coupling partner is reported. This method provides a pathway to prepare disubstituted cis-indanes in high diastereo- and enantioselectivities under mild reaction conditions. The proposed reaction mechanism includes enantioselective intermolecular migratory insertion and diastereoselective intramolecular allylation as the key elementary steps.
