Article
Chemistry, Organic
Yusuke Tomita, Naoto Haraguchi, Sayori Kiyota, Nobuyuki Komine, Masafumi Hirano
Summary: A traditional cobalt catalyst system has been found to exhibit previously undiscovered reactivity. Depending on the choice of tertiary phosphines and substrates, this catalytic system can catalyze diverse cycloadditions, yielding various cyclic compounds. The bite angles of the ligands used significantly contribute to the catalytic diversity.
Article
Chemistry, Multidisciplinary
Guolin Wu, Yuan Yao, Gen Li, Xue Zhang, Hui Qian, Shengming Ma
Summary: This study developed a catalytic recipe of copper halides to address the issues of side reactions and selectivity in the 1,5-H transfer of alka-1,4-diyn-3-yl amines, providing various allenynes with excellent enantioselectivities. The method was successfully applied to the first highly enantioselective total synthesis of the natural product scorodonin. Mechanistic studies and DFT calculations elucidated the regioselectivity for the observed 1,5-H transfer.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Toshimichi Ohmura, Yuta Takaoka, Michinori Suginome
Summary: The copper-catalyzed silafunctionalization of alkynes using silylboronic ester as a silicon source has made rapid progress. The trans-selective 1,2-addition of silylboronic esters to internal arylalkynes was efficiently promoted by the CuOt-Bu/RCy2P/NaOt-Bu catalysts, with a stereochemical switch to cis-addition observed in reactions utilizing Me-2(i-PrO)Si-B(pin) in hydrocarbon solvents including cyclohexane.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Yuichi Kobayashi, Yuji Takashima, Yuuya Motoyama, Yukari Isogawa, Kyosuke Katagiri, Atsuki Tsuboi, Narihito Ogawa
Summary: This study investigated the regioselectivity and enantiospecificity of substitution reactions of secondary propargylic alcohol derivatives using reagents derived from ArMgBr and Cu salts. The results showed that under certain reaction conditions, highly selective products could be obtained.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Kinga Stefanowska, Tomasz Sokolnicki, Jedrzej Walkowiak, Agnieszka Czapik, Adrian Franczyk
Summary: Hydrosilylation of borylalkynes to borylsilylalkenes (with a different arrangement of substituents) has been successfully developed using a specific catalyst, directing the cis-addition of the SiH group to the C-C bonds. The resulting products are crucial synthons for introducing C=C bonds in organic synthesis.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Applied
Saibal Singh, Graham E. Dobereiner
Summary: This study investigates the factors that control the selectivity of internal alkyne hydration using gold(I) catalysts and finds that the choice of solvent influences the selectivity. At ambient temperature, using [(IPr)Au(NCMe)][IMP-H] (C1) as a precatalyst is effective for the hydration of alkyl/alkyl and alkyl/aryl acetylenes.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Inorganic & Nuclear
Hiroto Yoshida, Yuki Izumi, Yuta Hiraoka, Kazuki Nakanishi, Masaaki Nakamoto, Sayaka Hatano, Manabu Abe
Summary: This article describes the synthesis of a new stable compound PhMe2Si-B(dan) and its application in catalytic silylboration and silylation reactions of alkynes.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Xue-Yi He, Zhong-Xia Wang
Summary: The synthesis of 1,4-enynes via nickel-catalyzed cross-coupling of allylic alcohols with alkynylzinc reagents exhibits high regio- and E/Z-selectivity, especially when aryl-substituted allylic alcohols are employed. The method also shows a wide scope of substrates and good compatibility of functional groups.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Bo-Ying Yao, Wei-Guo Xiao, Li-Jun Xiao, Qi-Lin Zhou
Summary: A method for hydroalkynylation reaction of 1,3-dienes with simple alkynes using an efficient nickel catalyst system and Xantphos ligand is presented. This method overcomes previous constraints in 1,3-diene hydroalkynylation and offers a convenient and direct means for obtaining a wide range of allylic alkynes.
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, Multidisciplinary
Qing He, Lei Zhu, Zhen-Hong Yang, Bo Zhu, Qin Ouyang, Wei Du, Ying-Chun Chen
Summary: In this study, a palladium(0) complex was used to mediate the unprecedented intermolecular coupling reactions of 1,3-enynes and N-sulfonylimines, resulting in the construction of enantioenriched all-carbon tetra-substituted alkene derivatives. By forming η(2)-complexes with the alkene moiety of 1,3-enynes, the palladium(0) acted as a pi-Lewis base catalyst to increase the nucleophilicity of the alkyne group, allowing for an enantioselective attack on the imines based on the principle of vinylogy. Additionally, a reductive coupling of 1,3-enynes and imines was achieved using formic acid as a hydrogen transfer reagent under palladium(0) catalysis.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Anastasia Louka, Manolis Stratakis
Summary: The study demonstrates that terminal alkynes react with unactivated digermane to form cis-1,2-digermylated alkenes under the catalysis of Au/TiO2; it also achieves the hydrogermylation of terminal allenes with a highly regioselective mode forming vinylgermanes on the more substituted double bond. Moreover, preliminary results are shown for the Pd nanoparticle-catalyzed C-C coupling of 1,2-digermyl alkenes with aryl iodides.
Review
Chemistry, Multidisciplinary
Sebastian M. Weber, Gerhard Hilt
Summary: This review outlines recent advances in chemo-, regio-, and stereoselective (cross-) dimerization of terminal alkynes to generate 1,3-enynes using various iron and cobalt catalysts with different oxidation states. The choice of ligands plays a crucial role in determining the stereoselectivity of the reaction, resulting in different product configurations.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Organic
Jinxia Li, Jinbo Luo, Wenyan Tong, Dingyi Tang, Jin Zhang, Zhi-Han Zhang, Shuanglin Qu
Summary: The transition metal catalyzed cycloaddition reaction is a powerful tool for constructing carbon- and heterocycles. Computational studies revealed the mechanism and origins of selectivities in the Ni-catalyzed intramolecular [4+2] cycloaddition. The reaction proceeds through oxidative addition/migratory insertion pathway, with the oxidative addition step determining the rate and enantioselectivity. The ligand dissociation during the reaction is critical and is favored for monodentate phosphine ligands but disfavored for bidentate phosphine ligands due to chelation effect.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Jinying Zhang, Bin Lu, Lingpeng Meng, Xiaoyan Li
Summary: Transitional metal catalyzed alkynes functionalization reaction is an atom-efficient, green, and sustainable method to synthesize functional molecules from triple bonds. In this study, the mechanism of alkyne hydrogermylation catalyzed by Co2(CO)8 was investigated using DFT calculations. The results reveal that the regioselectivity of the reaction is determined by the distribution of negative charges on the C1 and C2 atoms in alkynes.
MOLECULAR CATALYSIS
(2022)
