55816-27-8Relevant academic research and scientific papers
Copper-Mediated Cross-Coupling of Diazo Compounds with Sulfinates
Wang, Qian,Liu, An,Wang, Yan,Ni, Chuanfa,Hu, Jinbo
supporting information, p. 6919 - 6924 (2021/09/11)
A copper-mediated cross-coupling reaction between a diazo compound and a sodium alkane(arene)sulfinate gives a sulfone as the product. This reaction proceeds under mild conditions and features excellent functional group compatibility. A wide range of sodium alkane(arene)sulfinates were successfully applied in this chemistry. Mechanistic studies revealed that the overall reaction efficiency of the sulfinates was in line with their nucleophilicity in this reaction.
Dehalogenative Cross-Coupling of gem-Difluoroalkenes with Alkyl Halides via a Silyl Radical-Mediated Process
Tian, Hao,Yang, Shaoxiang,Wang, Xiaochen,Xu, Wentao,Liu, Yuxiu,Li, Yongqiang,Wang, Qingmin
supporting information, p. 12772 - 12782 (2021/09/13)
Herein, we describe a convenient general protocol for monofluoroalkenylation reactions of alkyl bromides involving cooperative visible-light photoredox catalysis and halogen abstraction. Mechanistic experiments showed that the products were generated by selective cross-coupling of aliphatic radicals with fluoroalkenyl radicals. Silyl radical-mediated halogen abstraction enabled the protocol to be used for the monofluoroalkenylation of a broad range of alkyl and heteroaryl halides. The protocol could be carried out on a gram scale and was applied to cholesterol, indicating its utility for late-stage monofluoroalkenylation reactions.
Enantioselective Diarylcarbene Insertion into Si-H Bonds Induced by Electronic Properties of the Carbenes
Evans, Declan,Houk, K. N.,Li, Mao-Lin,Li, Wen-Tao,Xu, Bin,Yang, Liang-Liang,Zhou, Qi-Lin,Zhu, Shou-Fei
supporting information, p. 12394 - 12399 (2020/08/06)
Catalytic enantioselection usually depends on differences in steric interactions between prochiral substrates and a chiral catalyst. We have discovered a carbene Si-H insertion in which the enantioselectivity depends primarily on the electronic characteristics of the carbene substrate, and the log(er) values are linearly related to Hammett parameters. A new class of chiral tetraphosphate dirhodium catalysts was developed; it shows excellent activity and enantioselectivity for the insertion of diarylcarbenes into the Si-H bond of silanes. Computational and mechanistic studies show how the electronic differences between the two aryls of the carbene lead to differences in energies of the diastereomeric transition states. This study provides a new strategy for asymmetric catalysis exploiting the electronic properties of the substrates.
Direct α-Monofluoroalkenylation of Heteroatomic Alkanes via a Combination of Photoredox Catalysis and Hydrogen-Atom-Transfer Catalysis
Tian, Hao,Xia, Qing,Wang, Qiang,Dong, Jianyang,Liu, Yuxiu,Wang, Qingmin
supporting information, p. 4585 - 4589 (2019/06/17)
In this study, a new C(sp3)-H monofluoroalkenylation reaction involving cooperative visible-light photoredox catalysis and hydrogen-atom-transfer catalysis to afford products generated by selective hydrogen abstraction and radical-radical cross-coupling was described. This mild, efficient reaction shows high regioselectivity for the α-carbon atoms of amines, ethers, and thioethers and thus allows the preparation of monofluoroalkenes bearing various substituents. The reaction was applied to two bioactive molecules, indicating its utility for late-stage monofluoroalkenylation of compounds with inert C(sp3)-H bonds.
Trifluoromethylation and Monofluoroalkenylation of Alkenes through Radical–Radical Cross-Coupling
Wang, Qiang,Qu, Yi,Tian, Hao,Liu, Yuxiu,Song, Hongjian,Wang, Qingmin
supporting information, p. 8686 - 8690 (2019/06/17)
The first visible-light-induced trifluoromethylation and monofluoroalkenylation of simple alkenes via a challenging radical–radical cross-coupling step was achieved. This method provided a mild, step-economical and redox-neutral route to privileged two different fluorinated difunctionalized allyl compounds. The utility of this method is illustrated by late-stage modification of medically important molecules.
Hypervalent-iodine(iii) oxidation of hydrazones to diazo compounds and one-pot nickel(ii)-catalyzed cyclopropanation
Liu, Haixuan,Wei, Yunyang,Cai, Chun
supporting information, p. 674 - 678 (2016/01/12)
A one-pot process for the catalytic cyclopropanation of various alkenes with unsubstituted hydrazones is described. Iodosobenzene (Ph = O) was found to be a competent oxidant of hydrazones to diazo compounds. Ni(OH)2 was chosen as an effective and cheap metal catalyst. The cyclopropane products can be generated efficiently (5 min-4 h) in moderate to good yields (42-91%) under mild (80°C) and neat conditions.
Microwave assisted solvent-free C-H amination by silica-supported manganese dioxide
Cao, Sufen,Duan, Wenhu
supporting information, p. 2390 - 2394 (2016/05/19)
An effective and convenient method has been developed for the preparation of 1-unsubstituted 1H-indazoles via C-H amination of N-acetylhydrazones in the presence of a catalytic amount of manganese dioxide under microwave irradiation. This new method featured easy operation and relatively short reaction-time.
Cross-Coupling between Difluorocarbene and Carbene-Derived Intermediates Generated from Diazocompounds for the Synthesis of gem-Difluoroolefins
Zheng, Jian,Lin, Jin-Hong,Yu, Liu-Ying,Wei, Yun,Zheng, Xing,Xiao, Ji-Chang
supporting information, p. 6150 - 6153 (2016/01/09)
Cross-coupling between difluorocarbene and carbene-derived intermediates generated from diazocompounds was developed to give gem-difluoroolefins, which constitutes a fast practical pathway to achieve hindered gem-difluoroolefins. The cross-coupling between difluorocarbene and aryl diazoacetates proceeded smoothly in the presence of a copper source, whereas its coupling with diaryl diazomethanes occurred well under metal-free conditions. A mechanism involving a copper-difluorocarbene complex was proposed.
Evaluation of some classical hydrazones of ketones and 1,2-diketones as antileishmanial, antibacterial and antifungal agents
Al-Kahraman, Yasser M.S.A.,Yasinzai, Masoom,Singh, Girija S.
experimental part, p. 1009 - 1013 (2012/10/08)
The paper describes the synthesis and antimicrobial (antileishmanial, antibacterial and antifungal) activity of some classical hydrazones of benzophenones and of 1,2-diketones. N-(Diaryl) acyl derivatives of these hydrazones have also been synthesized and evaluated. 4,4,- Demthoxybenzil monohydrazone and 4,4'-dimethoxybenzophenone hydrazone showed significant antileishmanial activity. The effect of substituents on the bioactivity is discussed.
Synthesis and biological activity of some 2-imidazolinylhydrazone derivatives
Kornicka, Anita,Hudson, Alan L.,Bednarski, Patrick J.
experimental part, p. 523 - 534 (2010/02/27)
A series of N-(imidazolidin-2-ylidene)hydrazones and N-(4,5-dihydro-1H- imidazol-2-yl)-N-methylhydrazones were prepared and examined for α1-, α2-adrenergic and imidazoline I 1, I2 receptors binding affinities as well as cytotoxic activity against human tumor cell lines. Among the compounds tested, 2-naphthaldehyde N-(imidazolidin-2-ylidene)hydrazone (3e) exhibited a significant affinity for both α2-adrenergic and imidazoline I1 receptors (Ki = 94.3 nM and IC50 = 51.7 nM, respectively). Moreover, pyridine-2-carboxaldehyde N-(imidazolidin-2-ylidene) hydrazone (3l) showed the highest binding affinity to α1- adrenoceptors (Ki = 24.6 nM), while quinoline-2-carboxaldehyde N-(imidazolidin-2-ylidene)hydrazone (3m) displayed the highest I2 affinity with a Ki value of 26.7 nM and a high selectivity with respect to α2-adrenergic and imidazoline I1 receptors (Ki = 22470.0 nM and IC50 = 6145.0 nM, respectively). None of the tested N-(4,5-dihydro-1H-imidazol-2-yl)-N- methylhydrazones 4p-u displayed cytotoxic activity.
