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Asymmetric Alkynylation of Tertiary Carbon-Centered Radical via Copper-Catalyzed Radical Relay

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Chinese Journal of Chemistry 2022年第14期40卷 1699-1704页

作者： Dunqi Wu Lianqian Wu pinhong chen Guosheng Liu Chang-Kung Chuang Institute East China Normal University3663 North Zhongshan RoadShanghai 200062China State Key Laboratory of Organometalic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical SynthesisCenter for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Alkynes are frequently found in a high proportion of natural products and bioactive moleculars,as well as a common synthon in organic synthesis,which can be easily transformed to an alkenyl,alkyl,heteroaryl,or carboxylic acid group.The enantioselective construction of alkyne substituted all carbon quaternary stereocenters is rarely reported and still a big challenge.As part of our continuous effort on developing asymmetric radical transformations,we found introducing an amidyl group(CONHAr)adjacent to the tertiary carbon radical could enable the asymmetric radical coupling with alkyne reagents.The amidyl group may stabilize the tertiary carbon radical or coordination with the chiral copper catalyst.Herein,we communicate a copper-catalyzed asymmetric trifluoromethyl-alkynylation ofα-aryl substituted acrylamides,which provides a straightforward and efficient access to chiral quaternary all-carbon centers bearing alkynyl groups in good yields and enantioselectivities.This reaction was also applied for the synthesis of chiral functionalized dipeptide.

关键词： Copper Asymmetric catalysis Asymmetric alkynylation Chiral quaternary carbon stereocenters Radicals

Cu/photoredox-catalyzed decarboxylative radical C(sp^(3))–C(sp^(3))cross-coupling reactions

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Science China Chemistry 2023年第10期66卷 2858-2862页

作者： Chao Jiang pinhong chen Guosheng Liu State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

A radical decarboxylative C(sp^(3))–C(sp^(3))cross-coupling of NHPI esters and cyclopropanols was developed by combining photocatalysis and copper catalysis,which presents the efficient access toβ-benzyl ketones in excellent yields.Terpyridin-4′-one used as the ligand is vital for the reaction,which could facilitate the capture of benzylic radicals by alkyl-copper species generated from copper-catalyzed ring-opening of cyclopropanols.The reaction exhibited broad substrate scope and wide functional group compatibility,providing an alternative approach for C(sp^(3))–C(sp^(3))bond formation.

关键词： copper catalysis C(sp^(3))-C(sp^(3))cross-coupling photoredox NHPI ester cyclopropanol

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Cu/photoredox-catalyzed decarboxylative radical C(sp)–C(sp)cross-coupling reactions

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Science China Chemistry 2023年

作者： Chao Jiang pinhong chen Guosheng Liu State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences

A radical decarboxylative C(sp3)–C(sp3) cross-coupling of NHPI esters and cyclopropanols was developed by combining photocatalysis and copper catalysis, which presents the efficient access to β-benzyl ketones in excellent yields. Terpyridin-4′-one used as the ligand is vital for the reaction, which could facilitate the capture of benzylic radicals by alkyl-copper species generated from copper-catalyzed ring-opening of cyclopropanols. The reaction exhibited broad substrate scope and wide functional group compatibility, providing an alternative approach for C(sp3)–C(sp3) bond formation.

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Enantioselective Arylcyanation of Styrenes via Copper-Catalyzed Radical Relay

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Chinese Journal of Chemistry 2021年第1期39卷 50-54页

作者： Weiwen Zhuang pinhong chen Guosheng Liu Key Laboratory of Organometallic Chemistry and Shanghai-Hong Kong Joint Llaboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China

The first copper-catalyzed enantioselective arylcyanation of styrenes has been developed using readily available anilines as aryl radical precursors under mild conditions,which enables easy access to chiral 2,3-diaryl propionitriles with moderate to good enantiose-lectivities.This operationally straightforward reaction exhibits broad substrate scope and functional group tolerance.Notably,this method has been applied to the synthesis of chiral AlEgen as well as estrogen receptor-B agonist(R)-diarylpropionitrile(DPN).

关键词： Copper catalysis Arylcyanation Asymmetric radical reactions Styrene Meerwein arylation

Palladium-Catalyzed Intermolecular Oxidative Diazidation of Alkenes

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Chinese Journal of Chemistry 2017年第6期35卷 876-880页

作者： Haihui Peng Zheliang Yuan pinhong chen Guosheng Liu State Key Laboratory of Organometallics Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A palladium-catalyzed oxidative vicinal diazidation of alkenes has been developed, in which TMSN3 was used as azide source. Both styrenes and unactivated alkenes are suitable for this reaction. And trans-alkyldiazides were obtained as major products from cyclic alkenes with moderate to good diastereoselectivities. This reaction afforded an efficient way for the synthesis of useful 1,2-diamines after hydrogenation.

关键词： palladium-catalyzed azidation alkene styrene

Palladium(Ⅱ)-Catalyzed Aminotrifluoromethoxylation of Alkenes:Mechanistic Insight into the Effect of N-Protecting Groups

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Chinese Journal of Chemistry 2020年第4期38卷 346-350页

作者： Chaohuang chen Chuanqi Hou pinhong chen Guosheng Liu State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai 200032China Shanghai Hongkong Joint Laboratory in Chemical Synthesis Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoodShanghai 200032China

Summary of main observation and conclusion An eficient palladium-atalyzed regioselective 5 exo aminotrifluoromethoxylation of alkenes has been established herein,which provides practical route towards the synthesis of OCF g-containing prrolidines.tert-Butyloxycarbonyl(Boc)as an amino pro-tecting group plays a signifiant role in both the chemo-and regloselectivities.In addition,preliminary mechanistic studies reveal that the amino protect-ing group of substrates and the counter anion of palladium catalyst play critical roles in reaction efficiency presumably due to an isomerization of alkyl-Pd(Ⅱ)intermediates.Moreover,the asymmetric 5-exo aminrifluoromethoxylation reaction has also been achieved by introducing a serelallyl bulky pyri-dinyl-oxazoline ligand.

关键词： palladium Palladium herein

Advances and challenges in palladium-catalyzed intermolecular selective allylic C–H functionalization of alkenes

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Science China Chemistry 2015年第8期58卷 1249-1251页

作者： Xiaoxu Qi pinhong chen Guosheng Liu State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Scieneces

During the past decade,there was increased interest in the functionalization of the allylic C–H bond of alkenes.As opposed to traditional Trost-Tsuji reactions,this strategy avoids the prefunctionalization of the alkene.Many transition metals have been used to promote such processes,and palladium has proved to be one of the best catalysts as

关键词：官能团化 C-H键烯丙基钯催化烯烃分子间和面过渡金属

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AgF-Mediated Dialkylation of Activate Alkenes: An Efficient Access to Nitrile-Containing Spirooxindoles

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Chinese Journal of Chemistry 2014年第8期32卷 681-684页

作者： Liang Wu pinhong chen Guosheng Liu State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A novel Ag-mediated dialkylation reaction of alkenes was disclosed,in which AgF was essential to activate C-H bond of acetonitrile.This reaction provided an efficient way to nitrile-containing spirooxindoles from read... 详细信息

关键词： spirooxindoles activated alkenes silver fluoride acetonitrile C-H bond cleavage

Iodine（Ⅲ） reagent（ABX–N3）-induced intermolecular anti-Markovnikov hydroazidation of unactivated alkenes

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Science China Chemistry 2019年第11期62卷 1537-1541页

作者： Xiaonan Li pinhong chen Guosheng Liu State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular Synthesis Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences Chinese Academy of Sciences

Anti-Markovnikov hydroazidation of unactivated alkenes using ABX–N3 as an initiator has been developed at room temperature,wherein hydrogen azide(HN3)acts as both hydrogen and azidating agent.Notably,the HN3 reagent was generated from azidotrimethylsilane(TMSN3)and acetic acid in situ.The reaction itself displays broad substrate scope,good yields and excellent regioselectivities.

关键词： anti-Markovnikov hydroazidation iodine(Ⅲ) reagent(ABX–N3) unactivated alkenes

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