Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction ...Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules,especially valuable N-heterocycles.However,successful examples of intermolecular generation ofα-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides.Herein,we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides,enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex-2-ene derivatives in good to excellent yields with excellent diastereoselectivities.Importantly,this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.展开更多
The Meinwald rearrangement has proven to be one of the most useful tools in organic synthesis.However,examples of asymmetric Meinwald rearrangements are quite scarce,and these reactions have so far been limited to the...The Meinwald rearrangement has proven to be one of the most useful tools in organic synthesis.However,examples of asymmetric Meinwald rearrangements are quite scarce,and these reactions have so far been limited to the use of chiral Br?nsted acids as catalysts.Here,we report a copper-catalyzed asymmetric cascade cyclization/Meinwald rearrangement reaction,allowing the practical and atom-economic synthesis of a range of chiral tricyclic pyrroles bearing a chiral oxa-quaternary carbon stereocenter in high yields and enantioselectivities.Thus,this protocol not only represents the first transition-metal-catalyzed enantioselective Meinwald rearrangement,but also constitutes the first example of asymmetric formal monocarbon insertion into C-O bond of ester.Moreover,theoretical calculations provide further evidence for this multiple cascade cyclization and elucidate the origin of enantioselectivity.展开更多
Conia-ene reactions,as a type of ene reactions,have not become a remarkable focus until the beginning of21st century,when Lewis acids served as powerful catalysts and found an increasingly broad utilization in this fi...Conia-ene reactions,as a type of ene reactions,have not become a remarkable focus until the beginning of21st century,when Lewis acids served as powerful catalysts and found an increasingly broad utilization in this field.Consequently,the catalytic Conia-ene reactions have gained great significance in synthetic chemistry due to their high efficiency and atom economy on the construction of valuable cyclic molecules.During the past two decades,the rapid development of transition-metal catalysis and organocatalysis has imposed a profound impact on the exploration of asymmetric Conia-ene reactions.As a result,several strategies have been developed and applied successfully.Organized on the basis of the catalytic system,this review comprehensively presents a summary of recent progress achieved in this emerging domain,aimed at highlighting the reactions’features,practicalities,and the mechanistic rationale is presented where possible.展开更多
Catalytic asymmetric dearomatization of indoles and alkynes has received much attention in the past decade because this strategy offers an attractive and alternative way for the efficient synthesis of valuable chiral ...Catalytic asymmetric dearomatization of indoles and alkynes has received much attention in the past decade because this strategy offers an attractive and alternative way for the efficient synthesis of valuable chiral polycyclic indolines. However, these reactions have been mostly limited to transition-metal catalysts, and the related chiral Br■nsted acid catalysis has been scarcely reported. Herein, we disclose a chiral phosphoric acid-catalyzed asymmetric dearomatization of indolyl ynamides by direct activation of alkynes. This metal-free method enables the practical and atom-economical construction of an array of valuable chiral polycyclic indolines in moderate to good yields with high enantioselectivities.展开更多
Bichner reaction,as a unique type of expansive dearomatization,has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic precursors.Although...Bichner reaction,as a unique type of expansive dearomatization,has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic precursors.Although the asymmetric version has been investigated since the early 1990s,enantioselective Bichner reaction is still limited by the catalyst type and substrate scope.This review aims to propose the limitation and possible development direction of this field by summarizing the evolution of catalytic asymmetric Bichner reaction,which is organized on the basis of intra-and intermolecular reactions.Considering the different metal carbene precursors,the reactions are further classified by carbene sources.展开更多
An efficient gold-catalyzed anti-Markovnikov cycloisomerization-initiated tandem reaction of Bocprotected indole tethered homopropargyl amides has been achieved.This method delivers a wide range of valuable bridged az...An efficient gold-catalyzed anti-Markovnikov cycloisomerization-initiated tandem reaction of Bocprotected indole tethered homopropargyl amides has been achieved.This method delivers a wide range of valuable bridged aza-[n.2.1]skeletons(n=3-7)at room temperature with high diastereoselectivity and enantioselectivity by a chirality-transfer strategy.Moreover,the gold-catalyzed tandem reaction of homopropargyl alcohol is also achieved to produce the bridged oxa-[3.2.1]skeleton.展开更多
High-efficiency phosphorescent materials serve as the cornerstone for the advancement of organic lightemitting diodes(OLEDs).It is well-established that the incorporation of nitrogen heterocycles and the modulation of...High-efficiency phosphorescent materials serve as the cornerstone for the advancement of organic lightemitting diodes(OLEDs).It is well-established that the incorporation of nitrogen heterocycles and the modulation of structural rigidity and conjugation can enhance the electron transfer capability and luminous efficiency of the complexes,which are indispensable for achieving high-performance devices.In this study,we report three iridium(III)complexes,namely(4-tfmptp)_(2)Ir(pic),(4-tfmptp)_(2)Ir(3-ppca),and(4-tfmptp)_(2)Ir(3-iqca).These complexes feature the rigid 4-tfmptp(4-[4-(trifluoromethyl)phenyl]thieno[2,3-d]pyrimidine)as the primary ligand,with pic(picolinic acid),3-ppca(pyrrolo[1,2-c]pyrimidine-3-carboxylic acid),and 3-iqca(isoquinoline-3-carboxylic acid)as the auxiliary ligands,respectively.In comparison to the complex(4-tfmptp)_(2)Ir(pic)based on the classic auxiliary ligand pic,the emission peaks of(4-tfmptp)_(2)Ir(3-ppca)and(4-tfmptp)_(2)Ir(3-iqca)remain largely unchanged,at around 568 nm.However,their photoluminescence quantum yields(PLQYs)in CH_(2)Cl_(2) improve remarkably,increasing from 53.6%to 93.6%and 97.2%,respectively.Furthermore,solution-processed OLEDs based on(4-tfmptp)_(2)Ir(3-ppca)and(4-tfmptp)_(2)Ir(3-iqca)exhibited exceptional device performances,with maximum current efficiencies of 74.2 and 91.4 cd A^(−1),and maximum external quantum efficiencies(EQE_(max))of 27.8%and 31.4%,respectively.These results suggest the modification of auxiliary ligand can affect the photophysical properties of the Ir(III)complexes greatly.展开更多
Transition metal-catalyzed cyclopropanation reactions of indoles are generally limited to diazo compounds.Herein,an efficient copper-catalyzed cyclopropanation reaction of indoles with N-propargyl ynamides is demonstr...Transition metal-catalyzed cyclopropanation reactions of indoles are generally limited to diazo compounds.Herein,an efficient copper-catalyzed cyclopropanation reaction of indoles with N-propargyl ynamides is demonstrated,allowing for practical and atom-economic construction of valuable cyclopropa[b]indolines in generally moderate to excellent yields under mild reaction conditions.Thus,this reaction constitutes a new way for cyclopropanation of indoles involving vinyl cations generated from diyne cyclization as key intermediates.Moreover,such an asymmetric cyclopropanation of indoles via chiral copper catalysis has also been realized.In addition,the formal C(sp^(2))–H functionalization of indoles is achieved by a one-pot copper-catalyzed diyne cyclization followed by proton acid-mediated ring-opening of cyclopropanes.展开更多
Herein,we disclose a highly regio-/chemoselective tandem asymmetric dearomatized halofunctionalization reaction of phenoltethered ynamides with diverse electrophilic halogenation sources in a catalyst-free manner for ...Herein,we disclose a highly regio-/chemoselective tandem asymmetric dearomatized halofunctionalization reaction of phenoltethered ynamides with diverse electrophilic halogenation sources in a catalyst-free manner for the practical and rapid assembly of a series of halogenated spirocyclic enones.Besides,the related dearomatized selenation and protonation are also achieved,affording the corresponding selenated and protonated spirocycles in high efficiency.Moreover,the enantioselectivities of these products can be perfectly induced by Evans auxiliaries(99%ees).Significantly,this protocol not only represents the first tandem asymmetric halofunctionalization reaction of phenol derivatives,but also constitutes the first asymmetric halogenation/selenation of ynamides.Theoretical calculations indicate a remote induction model of Evans chiral auxiliary-attached keteniminium.展开更多
Three novel iridium(III)complexes with pyrimidine carboxylic acid as the auxiliary ligand were designed,showing adjustable emission peak wavelengths from 559 nm to 610 nm with relatively high photoluminescence quantum...Three novel iridium(III)complexes with pyrimidine carboxylic acid as the auxiliary ligand were designed,showing adjustable emission peak wavelengths from 559 nm to 610 nm with relatively high photoluminescence quantum yields(PLQYs)of 58–89%in CH_(2)Cl_(2).The structures of the title complexes were confirmed by single-crystal X-ray diffraction(XRD),nuclear magnetic resonance spectroscopy(NMR),and high-resolution mass spectrometry(HRMS).Their electronic states were investigated using time-dependent density functional theory(TD-DFT)calculations.When employing these emitters to fabricate solution-processed organic light-emitting diodes(OLEDs),the obtained orange and red OLEDs exhibit prominent performances with the maximum current efficiencies of 95.4 cd A^(-1)and 39.8 cd A^(-1),and the maximum external quantum efficiencies(EQE_(max))of 31.3%and 24.7%,both of which are ranked among the highest values for orange and red solution-processed OLEDs.展开更多
Catalytic enantioselective preparation of axially chiral molecules has gained considerable interest over the past decades, due to their numerous applications in bioactive molecules, natural products, pharmaceuticals, ...Catalytic enantioselective preparation of axially chiral molecules has gained considerable interest over the past decades, due to their numerous applications in bioactive molecules, natural products, pharmaceuticals, materials, ligands, and catalysts. Compared with the well-established synthetic approaches for six-membered axially chiral skeletons, methodologies directed towards five-membered axially chiral compounds are relatively rare. Among these, axially chiral arylpyrroles are especially important structural motifs with wide utility, and the atroposelective synthesis of them is highly desirable. In recent years, novel strategies have been developed based on transition-metal catalysis and organocatalysis. This review summarizes the recent achievements in atroposelective preparation of arylpyrroles, by emphasizing the synthetic methods for each axially chiral framework, reaction mechanisms, and applications.展开更多
Summary of main observation and conclusion An efficient NaBAr^F4-catalyzed oxidative cyclization of readily available 1,5-and 1,6-diynes has been developed.Importantly,this transition metal-free oxidative catalysis pr...Summary of main observation and conclusion An efficient NaBAr^F4-catalyzed oxidative cyclization of readily available 1,5-and 1,6-diynes has been developed.Importantly,this transition metal-free oxidative catalysis proceeds via a presumable Lewis acid-catalyzed SN2′pathway,which is distinct from the relevant oxidative rhodium and gold catalysis.This method leads to the facile and practical construction of a diverse range of synthetically useful γ- and δ-lactams in mostly good to excellent yields with broad substrate scope.展开更多
Summary of main observation and conclusion An operationally simple and safe synthesis of a-haloketones using KBr and KCI as nonhazardous halogen sources is reported.It involves an iron-catalysed reaction of alkenes wi...Summary of main observation and conclusion An operationally simple and safe synthesis of a-haloketones using KBr and KCI as nonhazardous halogen sources is reported.It involves an iron-catalysed reaction of alkenes with KBr/KCl using O2 as terminal oxidant under the irradiation of visible-light.This strategy avoids the risks associated with handling halo-contained electrophiles(Cl2,Br2/NCS,NBS).The process is tolerant to several functional groups,and extended to a range of substituted styrenes in up to 89%yield.A radical reaction pathway is proposed based on control experiments and spectroscopy studies.展开更多
Gold-catalyzed nucleophilic addition to terminal alkynes has received considerable interest in the past decade, as this chemistry offers a highly efficient and regioselective way for CAC, CAH and CAX bond formation. H...Gold-catalyzed nucleophilic addition to terminal alkynes has received considerable interest in the past decade, as this chemistry offers a highly efficient and regioselective way for CAC, CAH and CAX bond formation. However, such a nucleophilic addition mainly involves a Markovnikov addition. In this short review, the recent progress of the gold-catalyzed 5-endo-dig cycloisomerization-initiated tandem reactions by utilizing the steric strain in ring formation to achieve an anti-Markovnikov regioselectivity was reviewed, including the scope of reactions, mechanism and synthetic applications.展开更多
The reduction of carboxamides into high value-added amines is a very interesting but great challenging topic.Herein we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient ca...The reduction of carboxamides into high value-added amines is a very interesting but great challenging topic.Herein we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient catalyst to reduce primary and secondary carboxamides to amines with excellent yield of 71%-98%and broad substrates scope.The methodology can extend to the gram-scale synthesis of phenethylamine drug with 93%yield.Based on the isolation and characterization of catalytic intermediates,a catalytic mechanism involving multipath reaction is proposed.This work provides efficient lanthanide cluster catalysts for the reduction of carboxamides to amines.展开更多
A non-noble metal catalyzed hydrative cyclization of aldehyde-ynamides for efficient and practical synthesis of medium-sized lactams(7-to 9-membered rings)is disclosed.Compared with previous hydrative cyclization for ...A non-noble metal catalyzed hydrative cyclization of aldehyde-ynamides for efficient and practical synthesis of medium-sized lactams(7-to 9-membered rings)is disclosed.Compared with previous hydrative cyclization for the formation of six-membered lactams(cis-form),a totally inverse diastereoselectivity(trans-form)of medium-sized lactams is observed.In addition,this protocol delivers valuable medium-sized lactams in moderate to good yields with high diastereoselectivities.Moreover,a rational mechanism to understand this inversion of diastereoselectivity is proposed based on theoretical calculations.展开更多
An efficient zinc-catalyzed oxidative cyclization of readily available indoly ynamides has been developed,enabling rapid and practical access to a diverse array of valuable medium-sized lactams in mostly good to excel...An efficient zinc-catalyzed oxidative cyclization of readily available indoly ynamides has been developed,enabling rapid and practical access to a diverse array of valuable medium-sized lactams in mostly good to excellent yields with wide substrate scope.In addition,such an asymmetric synthesis has also been explored by employing the chiral substrate.展开更多
α-Imino metal carbenes are versatile intermediates in organic synthesis,and have broad applications in the assembly of divergent N-heterocycles.However,the catalytic enantioselective desymmetrization based onα-imino...α-Imino metal carbenes are versatile intermediates in organic synthesis,and have broad applications in the assembly of divergent N-heterocycles.However,the catalytic enantioselective desymmetrization based onα-imino metal carbenes has not been developed to date.Herein,we disclose an enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides viaα-imino copper carbenes,leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high enantioselectivities.Notably,this reaction represents the first enantioselective desymmetrization based onα-imino metal carbenes.Further synthetic transformations and biological tests show the potential utility of this method.Moreover,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.展开更多
Catalytic asymmetric transformations of ynamides have attracted considerable attention in recent years.However,most of them were limited to intramolecular reactions or required metal catalysts.Herein,a chiral Br?nsted...Catalytic asymmetric transformations of ynamides have attracted considerable attention in recent years.However,most of them were limited to intramolecular reactions or required metal catalysts.Herein,a chiral Br?nsted acid-catalyzed asymmetric intermolecular[4+2]annulation of ynamides with para-quinone methides(p-QMs)is disclosed,which not only represents the first metal-free protocol for catalytic asymmetric nucleophilic addition of ynamides to electrophiles,but also constitutes the first enantioselective annulation between p-QMs and alkynes.This methodology leads to the practical synthesis of biologically important chiral 4-aryl-3,4-dihydrocoumarins and 4-aryl-coumarins.Preliminary control experiments indicate that the orthohydroxyphenyl substituted p-QMs could isomerize into ortho-quinone methides(o-QMs)in the presence of chiral catalyst,which further react with ynamides via enantioselective[4+2]annulation,to generate the chiral product.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.22125108,22331004 and 22121001)Yunnan Normal University,Applied Basic Research Projects of Yunnan Province(No.202101AT070217)+1 种基金the Jiangxi Provincial Natural Science Foundation(No.20224BAB213013)the Jiangxi Provincial Department of Education in Science and Technology Program Project(No.GJJ210906)。
文摘Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules,especially valuable N-heterocycles.However,successful examples of intermolecular generation ofα-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides.Herein,we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides,enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex-2-ene derivatives in good to excellent yields with excellent diastereoselectivities.Importantly,this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.
基金financial support from the National Natural Science Foundation of China(Nos.22125108,22101238,22331004 and 22121001)Yunnan Fundamental Research Project(No.202401CF070024)+2 种基金Natural Science Foundation of Jiangsu Province(No.BK20211059)the Project of Science and Technology of Xuzhou Government(No.KC22080)NFFTBS(No.J1310024)。
文摘The Meinwald rearrangement has proven to be one of the most useful tools in organic synthesis.However,examples of asymmetric Meinwald rearrangements are quite scarce,and these reactions have so far been limited to the use of chiral Br?nsted acids as catalysts.Here,we report a copper-catalyzed asymmetric cascade cyclization/Meinwald rearrangement reaction,allowing the practical and atom-economic synthesis of a range of chiral tricyclic pyrroles bearing a chiral oxa-quaternary carbon stereocenter in high yields and enantioselectivities.Thus,this protocol not only represents the first transition-metal-catalyzed enantioselective Meinwald rearrangement,but also constitutes the first example of asymmetric formal monocarbon insertion into C-O bond of ester.Moreover,theoretical calculations provide further evidence for this multiple cascade cyclization and elucidate the origin of enantioselectivity.
基金financial support from the National Natural Science Foundation of China(Nos.2170217,21772161)the Natural Science Foundation of Fujian Province of China(No.2019J02001)+3 种基金Natural Science Foundation of Shaanxi(No.2018JQ2072)the Youth Training Program of Northwest A&F University(No.2452016006)the President Research Funds from Xiamen University(No.20720180036),PCSIRTScience&Technology Cooperation Program of Xiamen(No.3502Z20183015)。
文摘Conia-ene reactions,as a type of ene reactions,have not become a remarkable focus until the beginning of21st century,when Lewis acids served as powerful catalysts and found an increasingly broad utilization in this field.Consequently,the catalytic Conia-ene reactions have gained great significance in synthetic chemistry due to their high efficiency and atom economy on the construction of valuable cyclic molecules.During the past two decades,the rapid development of transition-metal catalysis and organocatalysis has imposed a profound impact on the exploration of asymmetric Conia-ene reactions.As a result,several strategies have been developed and applied successfully.Organized on the basis of the catalytic system,this review comprehensively presents a summary of recent progress achieved in this emerging domain,aimed at highlighting the reactions’features,practicalities,and the mechanistic rationale is presented where possible.
基金financial support from the National Natural Science Foundation of China(Nos.22125108,22101238,92056104 and 21772161)the China Postdoctoral Science Foundation(No.2020M680087)+3 种基金the Natural Science Foundation of Fujian Province of China(No.2019J02001)the President Research Funds from Xiamen University(No.20720210002)the Fundamental Research Funds for the Central Universities(No.20720202008)NFFTBS(No.J1310024)。
文摘Catalytic asymmetric dearomatization of indoles and alkynes has received much attention in the past decade because this strategy offers an attractive and alternative way for the efficient synthesis of valuable chiral polycyclic indolines. However, these reactions have been mostly limited to transition-metal catalysts, and the related chiral Br■nsted acid catalysis has been scarcely reported. Herein, we disclose a chiral phosphoric acid-catalyzed asymmetric dearomatization of indolyl ynamides by direct activation of alkynes. This metal-free method enables the practical and atom-economical construction of an array of valuable chiral polycyclic indolines in moderate to good yields with high enantioselectivities.
基金support from MoST(No.2021YFC2100100)the National Natural Science Foundation of China(No.22125108)Yunnan Normal University,and Applied Basic Research Projects of Yunnan Province(No.202101AT070217).
文摘Bichner reaction,as a unique type of expansive dearomatization,has become a practical strategy for the straightforward assembly of valuable functionalized cycloheptatrienes from ubiquitous aromatic precursors.Although the asymmetric version has been investigated since the early 1990s,enantioselective Bichner reaction is still limited by the catalyst type and substrate scope.This review aims to propose the limitation and possible development direction of this field by summarizing the evolution of catalytic asymmetric Bichner reaction,which is organized on the basis of intra-and intermolecular reactions.Considering the different metal carbene precursors,the reactions are further classified by carbene sources.
基金financial support from the National Natural Science Foundation of China(Nos.21622204,21572186,21772161,21572163 and 21372178)the Natural Science Foundation of Fujian Province of China(No.2019J02001)+3 种基金the President Research Funds from Xiamen University(No.20720180036)NFFTBS(No.J1310024)PCSIRTScience&Technology Cooperation Program of Xiamen(No.3502Z20183015)。
文摘An efficient gold-catalyzed anti-Markovnikov cycloisomerization-initiated tandem reaction of Bocprotected indole tethered homopropargyl amides has been achieved.This method delivers a wide range of valuable bridged aza-[n.2.1]skeletons(n=3-7)at room temperature with high diastereoselectivity and enantioselectivity by a chirality-transfer strategy.Moreover,the gold-catalyzed tandem reaction of homopropargyl alcohol is also achieved to produce the bridged oxa-[3.2.1]skeleton.
基金supported by the National Natural Science Foundation of China(22365035,52203231)Yunnan Province Xingdian Talent Support Program for Young Talents,Expert Workstation in Yunnan Province(202405AF140035)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515110478)Shenzhen University Stability Support Program Project(20220818172424009)。
文摘High-efficiency phosphorescent materials serve as the cornerstone for the advancement of organic lightemitting diodes(OLEDs).It is well-established that the incorporation of nitrogen heterocycles and the modulation of structural rigidity and conjugation can enhance the electron transfer capability and luminous efficiency of the complexes,which are indispensable for achieving high-performance devices.In this study,we report three iridium(III)complexes,namely(4-tfmptp)_(2)Ir(pic),(4-tfmptp)_(2)Ir(3-ppca),and(4-tfmptp)_(2)Ir(3-iqca).These complexes feature the rigid 4-tfmptp(4-[4-(trifluoromethyl)phenyl]thieno[2,3-d]pyrimidine)as the primary ligand,with pic(picolinic acid),3-ppca(pyrrolo[1,2-c]pyrimidine-3-carboxylic acid),and 3-iqca(isoquinoline-3-carboxylic acid)as the auxiliary ligands,respectively.In comparison to the complex(4-tfmptp)_(2)Ir(pic)based on the classic auxiliary ligand pic,the emission peaks of(4-tfmptp)_(2)Ir(3-ppca)and(4-tfmptp)_(2)Ir(3-iqca)remain largely unchanged,at around 568 nm.However,their photoluminescence quantum yields(PLQYs)in CH_(2)Cl_(2) improve remarkably,increasing from 53.6%to 93.6%and 97.2%,respectively.Furthermore,solution-processed OLEDs based on(4-tfmptp)_(2)Ir(3-ppca)and(4-tfmptp)_(2)Ir(3-iqca)exhibited exceptional device performances,with maximum current efficiencies of 74.2 and 91.4 cd A^(−1),and maximum external quantum efficiencies(EQE_(max))of 27.8%and 31.4%,respectively.These results suggest the modification of auxiliary ligand can affect the photophysical properties of the Ir(III)complexes greatly.
基金the National Natural Science Foundation of China(22125108,22331004)the Natural Science Foundation of Fujian Province of China(2024H6022)+1 种基金Natural Science Foundationof Jiangsu Province(BK20211059)the Project of Science and Technology of Xuzhou Government(KC22080).
文摘Transition metal-catalyzed cyclopropanation reactions of indoles are generally limited to diazo compounds.Herein,an efficient copper-catalyzed cyclopropanation reaction of indoles with N-propargyl ynamides is demonstrated,allowing for practical and atom-economic construction of valuable cyclopropa[b]indolines in generally moderate to excellent yields under mild reaction conditions.Thus,this reaction constitutes a new way for cyclopropanation of indoles involving vinyl cations generated from diyne cyclization as key intermediates.Moreover,such an asymmetric cyclopropanation of indoles via chiral copper catalysis has also been realized.In addition,the formal C(sp^(2))–H functionalization of indoles is achieved by a one-pot copper-catalyzed diyne cyclization followed by proton acid-mediated ring-opening of cyclopropanes.
基金supported by the National Natural Science Foundation of China(22125108 and 22121001 for Ye LW,22122109 and 22271253 for Hong X)the National Key R&D Program of China(2022YFA1504301,Hong X)+8 种基金the Zhejiang Provincial Natural Science Foundation of China(LDQ23B020002,Hong X)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(SNZJU-SIAS-006,Hong X)the Beijing National Laboratory for Molecular Sciences(BNLMS202102,Hong X)the CAS Youth Interdisciplinary Team(JCTD-2021-11,Hong X)the Fundamental Research Funds for the Central Universities(226-2022-00140,226-2022-00224,and 226-2023-00115,Hong X)the State Key Laboratory of Physical Chemistry of Solid Surfaces(202210,Hong X)the Leading Innovation Team grant from the Department of Science and Technology of Zhejiang Province(2022R01005,Hong X)the Natural Science Foundation of Jiangsu Province(BK20211059)National Found for Fostering Talents of Basic Science(NFFTBS,J1310024).
文摘Herein,we disclose a highly regio-/chemoselective tandem asymmetric dearomatized halofunctionalization reaction of phenoltethered ynamides with diverse electrophilic halogenation sources in a catalyst-free manner for the practical and rapid assembly of a series of halogenated spirocyclic enones.Besides,the related dearomatized selenation and protonation are also achieved,affording the corresponding selenated and protonated spirocycles in high efficiency.Moreover,the enantioselectivities of these products can be perfectly induced by Evans auxiliaries(99%ees).Significantly,this protocol not only represents the first tandem asymmetric halofunctionalization reaction of phenol derivatives,but also constitutes the first asymmetric halogenation/selenation of ynamides.Theoretical calculations indicate a remote induction model of Evans chiral auxiliary-attached keteniminium.
基金National Natural Science Foundation of China(52203231 and 22365035)Guangdong Basic and Applied Basic Research Foundation(2021A1515110478)+2 种基金Shenzhen University Stability Support Program Project(20220818172424009)Applied Basic Research Projects of Yunnan Province(202101AT070217)Yunnan Normal University Postgraduate Research Innovation Fund(YJSJJ23-B128)。
文摘Three novel iridium(III)complexes with pyrimidine carboxylic acid as the auxiliary ligand were designed,showing adjustable emission peak wavelengths from 559 nm to 610 nm with relatively high photoluminescence quantum yields(PLQYs)of 58–89%in CH_(2)Cl_(2).The structures of the title complexes were confirmed by single-crystal X-ray diffraction(XRD),nuclear magnetic resonance spectroscopy(NMR),and high-resolution mass spectrometry(HRMS).Their electronic states were investigated using time-dependent density functional theory(TD-DFT)calculations.When employing these emitters to fabricate solution-processed organic light-emitting diodes(OLEDs),the obtained orange and red OLEDs exhibit prominent performances with the maximum current efficiencies of 95.4 cd A^(-1)and 39.8 cd A^(-1),and the maximum external quantum efficiencies(EQE_(max))of 31.3%and 24.7%,both of which are ranked among the highest values for orange and red solution-processed OLEDs.
基金supported by the National Natural Science Foundation of China (22125108, 92056104)the Fundamental Research Funds for the Central Universities (20720210002, 20720230003)the National Science Fund for Fostering Talents in Basic Science (J1310024)。
文摘Catalytic enantioselective preparation of axially chiral molecules has gained considerable interest over the past decades, due to their numerous applications in bioactive molecules, natural products, pharmaceuticals, materials, ligands, and catalysts. Compared with the well-established synthetic approaches for six-membered axially chiral skeletons, methodologies directed towards five-membered axially chiral compounds are relatively rare. Among these, axially chiral arylpyrroles are especially important structural motifs with wide utility, and the atroposelective synthesis of them is highly desirable. In recent years, novel strategies have been developed based on transition-metal catalysis and organocatalysis. This review summarizes the recent achievements in atroposelective preparation of arylpyrroles, by emphasizing the synthetic methods for each axially chiral framework, reaction mechanisms, and applications.
基金the National Natural Science Foundation of China (21572186,21622204 and 21772161)the President Research Funds from Xiamen University (20720180036)PCSIRT,XMU Undergraduate Innovation and Entrepreneurship Training Programs,and NFFTBS (J1310024).
文摘Summary of main observation and conclusion An efficient NaBAr^F4-catalyzed oxidative cyclization of readily available 1,5-and 1,6-diynes has been developed.Importantly,this transition metal-free oxidative catalysis proceeds via a presumable Lewis acid-catalyzed SN2′pathway,which is distinct from the relevant oxidative rhodium and gold catalysis.This method leads to the facile and practical construction of a diverse range of synthetically useful γ- and δ-lactams in mostly good to excellent yields with broad substrate scope.
基金We thank the financial support from the National Natural Science Foundation of China(Nos.21622204 and 21772161).
文摘Summary of main observation and conclusion An operationally simple and safe synthesis of a-haloketones using KBr and KCI as nonhazardous halogen sources is reported.It involves an iron-catalysed reaction of alkenes with KBr/KCl using O2 as terminal oxidant under the irradiation of visible-light.This strategy avoids the risks associated with handling halo-contained electrophiles(Cl2,Br2/NCS,NBS).The process is tolerant to several functional groups,and extended to a range of substituted styrenes in up to 89%yield.A radical reaction pathway is proposed based on control experiments and spectroscopy studies.
基金supported by the National Natural Science Foundation of China(21272191,21572186 and 21622204)the Natural Science Foundation of Fujian Province for Distinguished Young Scholars(2015J06003)+1 种基金the President Research Funds from Xiamen University(20720150045)NFFTBS(J1310024)
文摘Gold-catalyzed nucleophilic addition to terminal alkynes has received considerable interest in the past decade, as this chemistry offers a highly efficient and regioselective way for CAC, CAH and CAX bond formation. However, such a nucleophilic addition mainly involves a Markovnikov addition. In this short review, the recent progress of the gold-catalyzed 5-endo-dig cycloisomerization-initiated tandem reactions by utilizing the steric strain in ring formation to achieve an anti-Markovnikov regioselectivity was reviewed, including the scope of reactions, mechanism and synthetic applications.
基金supported by the National Natural Science Foundation of China(92161104,21871224,92161203,21721001)。
文摘The reduction of carboxamides into high value-added amines is a very interesting but great challenging topic.Herein we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient catalyst to reduce primary and secondary carboxamides to amines with excellent yield of 71%-98%and broad substrates scope.The methodology can extend to the gram-scale synthesis of phenethylamine drug with 93%yield.Based on the isolation and characterization of catalytic intermediates,a catalytic mechanism involving multipath reaction is proposed.This work provides efficient lanthanide cluster catalysts for the reduction of carboxamides to amines.
基金supported by the National Natural Science Foundation of China(92056104 and 21772161)the Natural Science Foundation of Fujian Province of China(2019J02001)+3 种基金the President Research Funds from Xiamen University(20720210002)the National Fund for Fostering Talents of Basic Science(NFFTBS)(J1310024)the Opening Project of PCOSS,Xiamen University(201909)the Bioinformatics Center of Nanjing Agricultural University and the Start-up Research Fund of Nanjing Agricultural University(050-804099)。
文摘A non-noble metal catalyzed hydrative cyclization of aldehyde-ynamides for efficient and practical synthesis of medium-sized lactams(7-to 9-membered rings)is disclosed.Compared with previous hydrative cyclization for the formation of six-membered lactams(cis-form),a totally inverse diastereoselectivity(trans-form)of medium-sized lactams is observed.In addition,this protocol delivers valuable medium-sized lactams in moderate to good yields with high diastereoselectivities.Moreover,a rational mechanism to understand this inversion of diastereoselectivity is proposed based on theoretical calculations.
基金the National Natu-ral Science Foundation of China(Nos.21572186,21622204 and 21772161)the Natural Science Foundation of Fujian Province of China(No.2019J02001)+2 种基金the President Research Funds from Xia-men University(No.20720180036)NFFTBS(No.J1310024)PCSIRT,and Science&Technology Cooperation Program of Xia-men(No.3502220183015).
文摘An efficient zinc-catalyzed oxidative cyclization of readily available indoly ynamides has been developed,enabling rapid and practical access to a diverse array of valuable medium-sized lactams in mostly good to excellent yields with wide substrate scope.In addition,such an asymmetric synthesis has also been explored by employing the chiral substrate.
基金supported by the National Natural Science Foundation of China(22331004,22125108 and 22121001)the National Fund for Fostering Talents of Basic Science NFFTBS(J1310024)。
文摘α-Imino metal carbenes are versatile intermediates in organic synthesis,and have broad applications in the assembly of divergent N-heterocycles.However,the catalytic enantioselective desymmetrization based onα-imino metal carbenes has not been developed to date.Herein,we disclose an enantioselective desymmetrizing C(sp^(2))-H functionalization of azide-ynamides viaα-imino copper carbenes,leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high enantioselectivities.Notably,this reaction represents the first enantioselective desymmetrization based onα-imino metal carbenes.Further synthetic transformations and biological tests show the potential utility of this method.Moreover,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.
基金supported by the Ministry of Science and Technology(MOST)(2021YFC2100100)the National Natural Science Foundation of China(22125108,22121001,92056104)+3 种基金the President Research Funds from Xiamen University(20720210002)the Natural Science Foundation of Jiangsu Province(BK20211059)the Project of Science and Technology of Xuzhou Government(KC22080)the National Fund for Fostering Talents of Basic Science(NFFTBS)(J1310024)。
文摘Catalytic asymmetric transformations of ynamides have attracted considerable attention in recent years.However,most of them were limited to intramolecular reactions or required metal catalysts.Herein,a chiral Br?nsted acid-catalyzed asymmetric intermolecular[4+2]annulation of ynamides with para-quinone methides(p-QMs)is disclosed,which not only represents the first metal-free protocol for catalytic asymmetric nucleophilic addition of ynamides to electrophiles,but also constitutes the first enantioselective annulation between p-QMs and alkynes.This methodology leads to the practical synthesis of biologically important chiral 4-aryl-3,4-dihydrocoumarins and 4-aryl-coumarins.Preliminary control experiments indicate that the orthohydroxyphenyl substituted p-QMs could isomerize into ortho-quinone methides(o-QMs)in the presence of chiral catalyst,which further react with ynamides via enantioselective[4+2]annulation,to generate the chiral product.
