Carbon dioxide(CO_(2))serves as a sustainable carbon source for building biomass,fossil fuels,and organic chemicals.Converting CO_(2) into value-added chemicals or fuels is an ideal approach to achieve carbon cycling....Carbon dioxide(CO_(2))serves as a sustainable carbon source for building biomass,fossil fuels,and organic chemicals.Converting CO_(2) into value-added chemicals or fuels is an ideal approach to achieve carbon cycling.The reduction and conversion of CO_(2),a pivotal aspect of C1 chemistry,have long been a subject of intense research interest.Previous studies have demonstrated that through transition metal catalysis,hydrogen,boranes,and silanes(E-H,E=H,B or Si)act as effective reducing agents to transform CO_(2) into a range of C1 chemicals,such as formate,formaldehyde,and methanol.Over the past decade,research focus in this field has shifted towards utilizing cost-effective metals as catalysts for selective CO_(2) reduction.A comprehensive review of homogeneous iron-catalyzed CO_(2)reduction using E-H is presented,emphasizing reaction mechanisms and selectivity.展开更多
An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources ...An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.展开更多
The synthesis of bo rylated orga nofluorines is of great interest due to their potential values as synthons in modular construction of fluorine-containing molecules.Reported herein is a rhodium-catalyzed hydrobo ratio...The synthesis of bo rylated orga nofluorines is of great interest due to their potential values as synthons in modular construction of fluorine-containing molecules.Reported herein is a rhodium-catalyzed hydrobo ration of arylgem-difluoroalkenes leading to a series of α-difluoromethylated benzylborons.The use of cationic rhodium catalyst and a biphosphine ligand with large bite angle was crucial for reactivity by offering good regioselectivity and diminishing the undesired β-F elimination.Preliminary derivatizations of the products were conducted to showcase the utility of this protocol.展开更多
We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of ...We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of unsaturated organic compounds.Both 1 and 2 react with HBpin by adding the B-H bond across the Ni-X bond (X=O or N),giving rise to the 18-electron Ni(II)-H active species,[H1(Bpin)]and[H_(2)(Bpin)].Subtle tuning of the Ni-X pair and the supporting ancillary phosphine have a significant effect on the reactivity and catalytic performance of Cp*Ni(1,2-R_(2)PC_(6)H_(4)X).Unlike[H_(2)(Bpin)],the activation of HBpin in[H1(Bpin)]is reversible,which enables the Ni-O complex to be an effective cooperative catalyst in the hydroboration of N-heteroarenes,and as well as ketones and imines.展开更多
Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective.In this respect,catalytic deoxygenative amide reduction has proven to be promising but challen...Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective.In this respect,catalytic deoxygenative amide reduction has proven to be promising but challenging,as this approach necessitates selective C-O bond cleavage.Herein,we report the selective hydroboration of primary,secondary,and tertiary amides at room temperature catalyzed by an earth-abundant-metal catalyst,Zr-H,for accessing diverse amines.Various readily reducible functional groups,such as esters,alkynes,and alkenes,were well tolerated.Furthermore,the methodology was extended to the synthesis of bio-and drug-derived amines.Detailed mechanistic studies revealed a reaction pathway entailing aldehyde and amido complex formation via an unusual C-N bond cleavage-reformation process,followed by C-O bond cleavage.展开更多
The trans-hydroboration of alkyne represents a challenging task in organic synthesis.Reported herein is an Et2 Zn promotedβ-trans hydroboration of ynamides by using N-heterocyclic carbene(NHC)-ligated borane as boryl...The trans-hydroboration of alkyne represents a challenging task in organic synthesis.Reported herein is an Et2 Zn promotedβ-trans hydroboration of ynamides by using N-heterocyclic carbene(NHC)-ligated borane as boryl source.The reaction leads to a stereoselective construction of enamides bearing a valuable boryl substituent.Both aromatic and aliphatic ynamides were applicable to the reaction.Synthetic transformation of the C-B bond in the product via Suzuki-Miyaura coupling provides a simple and stereospecific route to multi-substituted enamides.Mechanistic studies were conducted and the possible mechanism was discussed.展开更多
The symmetrical diketone Ⅱ, which can be synthesized in gram scale using a well established method, was used as a starting material to prepare the 11α-methoxy ketomethylene Ⅵ. This is in continuation of our study a...The symmetrical diketone Ⅱ, which can be synthesized in gram scale using a well established method, was used as a starting material to prepare the 11α-methoxy ketomethylene Ⅵ. This is in continuation of our study aiming at the synthesis of multihydroxylated cephalostatin analogues, as for example cephalostatin 1Ⅰ, a potent anti-tumor natural product. Compound Ⅵ underwent chemo- and regioselective hydroboration reaction at only one of △14.15 double bonds furnishing compound Ⅸ as a major product in a fair yield.展开更多
In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric a...In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric analysis,and energy-dispersive X-ray spectroscopy revealed that an Anderson-type POM,(NH4)4[CuMo6O18(OH)6]·5H2O was successfully immobilized on the sponge based on electrostatic interactions.Morphological analysis indicated that the POM-loaded sponge retained its porous structure and that the POM was homogeneously distributed on the sponge walls.The POM-loaded sponge exhibited excellent mechanical properties by recovering 79.9%of its original thickness following a 60%compression strain.The POM-loaded sponge was found to effectively catalyze the hydroboration of phenylacetylenes,yielding excellent conversion and regioselectivity of up to 96%and 99%,respectively.Its catalytic activity remained unchanged after five reuse cycles.These findings represent a scalable strategy for immobilizing POMs on porous supports.展开更多
Organoboron compounds are highly versatile building blocks in modern organic synthesis,pharmaceuticals,and materials science,offering unique reactivity and stability for the assembly of complex molecular structures.Th...Organoboron compounds are highly versatile building blocks in modern organic synthesis,pharmaceuticals,and materials science,offering unique reactivity and stability for the assembly of complex molecular structures.The hydroboration of allenes stands out as a straightforward method for the preparation of allyl and alkenyl boranes.Nonetheless,achieving precise control over regio-and stereoselectivity in these reactions presents significant challenges.In this review,we have systematically summarized the selective hydroboration of allenes catalyzed by a range of transition metals,including platinum,copper,palladium,cobalt,nickel,and ruthenium catalysts.The significant advancements,current limitations,and future perspective for the transition metal-catalyzed selective hydroboration are also highlighted.Moreover,we hope that this review will help understand more about the catalytic hydroboration of allenes and stimulate the further development of both allene and organoboron chemistry.展开更多
Arylidenecyclopropanes(ACPs)are highly strained substrates that can be readily utilized for diverse transformations.This study showcases the outcomes of copper-catalyzed ring-opening hydrosilylation and hydroboration ...Arylidenecyclopropanes(ACPs)are highly strained substrates that can be readily utilized for diverse transformations.This study showcases the outcomes of copper-catalyzed ring-opening hydrosilylation and hydroboration reactions of ACPs,showcasing precise cleavage of C—C bonds.The reaction presents an effective and convenient method for producing homoallylic silanes and boronates.展开更多
Selective reduction of readily available N-heteroarenes is important in both organic synthesis and chemical biology.Herein,we describe ligand-controlled regiodivergent hydroboration of quinolines using well-defined am...Selective reduction of readily available N-heteroarenes is important in both organic synthesis and chemical biology.Herein,we describe ligand-controlled regiodivergent hydroboration of quinolines using well-defined amido-manganese catalysts,with an emphasis on the rarely reported 1,4-regioselectivity.Mechanistic studies showed that 1,2-hydroboration of quinoline was kinetically favorable and reversible,whereas 1,4-hydroboration was under thermodynamic control.Using a 1-methyimidazolebased pincer amido-manganese complex as the catalyst,cooperative C-H…N andπ…πnoncovalent interactions between the 1-methyimidazole moiety and quinoline substrates enabled kinetic accessibility of 1,4-hydroboration,giving thermodynamically favored 1,4-hydroborated quinolines as the major products.On this basis,Mn-catalyzed 1,4-hydroboration of a series of substituted quinolines proceeded smoothly in high yields.A high turnover number of 2500 was achieved in this reaction with satisfying regioselectivity.This transformation could be further applied to the C3-selective functionalization of quinolines,highlighting the synthetic utility of this methodology.In contrast,using a pyridine-based pincer amido-manganese complex as the catalyst,which lacked the C-H…N interaction,the free-energy barrier for 1,4-hydroboration significantly increased through a N-B…N interaction between the“HMn-NB”species and quinoline,resulting in the kinetically favored 1,2-hydroboration product with excellent regioselectivity.展开更多
The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the ...The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the effect of the coordination structure of active metal centers on the catalytic activities for the design of such catalysts.Here,we report that different coordination structures of SA Pt catalysts can dramatically influence their activities for anti-Markovnikov hydroboration of alkenes.Compared with the other two coordination structures(Pt-N4 and Pt-O2),the SA Pt species coordinated with three O atoms(Pt-O3)display the highest turnover number value of 3288 for the hydroboration reaction to access the important alkylboronic esters.Density functional theory calculations reveal that a superior catalytic activity can be expected for alkene hydroboration over the three O coordinated Pt species due to the lowest reaction energy(ΔG)limiting step from the reaction phase diagram.展开更多
Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2...Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2-hydroboration to form allylboronates, while the FOXAP-cobalt(FOXAP=(S)-1-(diphenylphosphino)-2-[(S)-4-isopropyloxazolin-2-yl]ferrocene) catalyst effects the complementary anti-Markonikv 1,2-hydroboration to afford homoallyboronates with high regioselectivity.展开更多
Main observation and conclusion In this work,a novel mode for the activation of N-heterocyclic carbene boranes(NHC-boranes)was developed by generating the highly reactive zwitterion species through hydride abstraction...Main observation and conclusion In this work,a novel mode for the activation of N-heterocyclic carbene boranes(NHC-boranes)was developed by generating the highly reactive zwitterion species through hydride abstraction with Lewis acid B(C_(6)F_(5))_(3) in an frustrated Lewis pairs manner.A broad range of alkenes including stilbenes,β-methylstyrenes,styrenes,and alkyl-alkenes were suitable substrates for the B(C_(6)F_(5))_(3)-catalyzed hydroboration to furnish the desired products in good to high yields.Significantly,excellent regioselectivities were obtained in some cases.Mechanistic studies indicate that the B-H bond cleavage is likely involved in the rate-determining step.In addition,an electrophilic addition of NHC-borenium cation to alkenes and the subsequent formation of carbocation are also postulated.The current work provides a promising method for the activation of stable borane adducts,which might lead to some interesting transformations in the future.展开更多
We have previously reported that the Ti complex generated from Cp2TiCl2 and LiBH4 serves as a catalyst for hydroboration of alkenes. Sodium borohydride can also be utilized as a reagent for hydroboration if reaction i...We have previously reported that the Ti complex generated from Cp2TiCl2 and LiBH4 serves as a catalyst for hydroboration of alkenes. Sodium borohydride can also be utilized as a reagent for hydroboration if reaction is carried out in the pre-展开更多
The strong oxophilicity of actinide complexes prevents their applications in the transformation of oxygen-containing substrates.Herein,we report the use of a uranium(Ⅳ)alkyl complex as a catalyst for the hydroboratio...The strong oxophilicity of actinide complexes prevents their applications in the transformation of oxygen-containing substrates.Herein,we report the use of a uranium(Ⅳ)alkyl complex as a catalyst for the hydroboration of carbonyl compounds.This reaction has good functional group tolerance and chemo-selectivity under mild conditions.This study represents the rare example of catalytic reaction promoted by a uranium alkyl complex and highlights the potential of uranium complexes in synthetic chemistry.展开更多
The sustainable development of synthetic reactions catalyzed by earth-abundant metals is one of the principal goals in homogeneous catalysis.However,so far most of the protocols are still plagued by sophisticated liga...The sustainable development of synthetic reactions catalyzed by earth-abundant metals is one of the principal goals in homogeneous catalysis.However,so far most of the protocols are still plagued by sophisticated ligands,hazardous activators,high catalyst loading(1—10 mol%)and/or multistep synthesis of the metal complexes in the process development.Consequently,the development of earth-abundant metal catalysts with high activity from commercially available metal salts is highly desirable for practical utilization of base metal catalyzed synthetic methodology.Herein,we report the catalyst generated in situ from a mixture of catalytic amounts of Ni(acac)_(2)(as low as 0.005 mol%)and CsF,which is found highly active for Markovnikov-selective hydroboration of vinylarenes,including 1,1-disubstituted vinylarenes and internal olefins,affording a wide range of secondary and tertiary alkyl boronates in excellent yields.Mechanistic experiments indicate that the key to the success of this catalysis is the use of CsF,which in combination with pinacolborane acts as an effective activator for Ni(acac)_(2),probably generating metastable Ni nanoparticles in situ that demonstrate high activity in the catalytic hydroboration(TON up to 18800).展开更多
Polyketides,a large class of secondary metabolites,have been of long-standing interest to the synthetic community due to their intriguing biological activities and structural versatility and complexity.A typical struc...Polyketides,a large class of secondary metabolites,have been of long-standing interest to the synthetic community due to their intriguing biological activities and structural versatility and complexity.A typical structural unit of various natural products,polypropionate,has prompted enormous efforts in the development of novel synthetic methods and strategies in the past five decades.In this study,a non-aldol-type approach based on double hydroboration of allenes has been developed to provide a powerful method for the stereodivergent construction of various polyol stereotriads and stereotetrads that are amenable for synthesizing polypropionates.The stereochemical control is possibly attributable to the boronate complex that aligned itself as a rigid conformation for the second stereoselective hydroboration reaction by suppressing the barotropic rearrangement of allylborane intermediates.The feasibility of preparing the key polypropionate motif facilitates the efficient synthesis of(-)-pironetin,a potentα-tubulin inhibitor halting the cell cycle at M phase.展开更多
A new class of iron（II） hydrides based on a tetradentate PSNP ligand were synthesized and fully characterized. All the iron（II） complexes feature a folded PSNP ligand with cis reactive sites. The hydrido iron comp...A new class of iron（II） hydrides based on a tetradentate PSNP ligand were synthesized and fully characterized. All the iron（II） complexes feature a folded PSNP ligand with cis reactive sites. The hydrido iron complex [2 H（NCMe[2_TD$IF]1）]（BF4） is capable of catalyzing aldehyde hydroboration by pinacolborane（HBpin） and with extremely high efficiency at room temperature. Aldehydes with various functional groups are compatible.展开更多
文摘Carbon dioxide(CO_(2))serves as a sustainable carbon source for building biomass,fossil fuels,and organic chemicals.Converting CO_(2) into value-added chemicals or fuels is an ideal approach to achieve carbon cycling.The reduction and conversion of CO_(2),a pivotal aspect of C1 chemistry,have long been a subject of intense research interest.Previous studies have demonstrated that through transition metal catalysis,hydrogen,boranes,and silanes(E-H,E=H,B or Si)act as effective reducing agents to transform CO_(2) into a range of C1 chemicals,such as formate,formaldehyde,and methanol.Over the past decade,research focus in this field has shifted towards utilizing cost-effective metals as catalysts for selective CO_(2) reduction.A comprehensive review of homogeneous iron-catalyzed CO_(2)reduction using E-H is presented,emphasizing reaction mechanisms and selectivity.
基金Financial support from the National Science Foundation of China (No. 21202049)the Recruitment Program of Global Experts (1000 Talents Plan)+2 种基金Fujian Hundred Talents PlanProgram of Innovative Research Team of Huaqiao UniversityInstrumental Analysis Center of Huaqiao University for analysis support
文摘An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis（pinacolato）diboron was developed, affording b-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.
基金financial support from the National Natural Science Foundation of China(No.21971261)Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery(No.2019B030301005)+1 种基金Key Project of Chinese National Programs for Fundamental Research and Development(No.2016YFA0602900)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Y093)is gratefully acknowledged。
文摘The synthesis of bo rylated orga nofluorines is of great interest due to their potential values as synthons in modular construction of fluorine-containing molecules.Reported herein is a rhodium-catalyzed hydrobo ration of arylgem-difluoroalkenes leading to a series of α-difluoromethylated benzylborons.The use of cationic rhodium catalyst and a biphosphine ligand with large bite angle was crucial for reactivity by offering good regioselectivity and diminishing the undesired β-F elimination.Preliminary derivatizations of the products were conducted to showcase the utility of this protocol.
基金the financial support from the National Natural Science Foundation of China (Nos. 22022102 and 22071010)the financial support from China Postdoctoral Science Foundation (No. 2021M700462)。
文摘We report two air-stable nickel(II) half-sandwich complexes,Cp*Ni(1,2-Cy_(2)PC_(6)H_(4)O)(1) and Cp*Ni(1,2-Ph_(2)PC_(6)H4NH)(2),for cooperative B-H bond activation and their applications in catalytic hydroboration of unsaturated organic compounds.Both 1 and 2 react with HBpin by adding the B-H bond across the Ni-X bond (X=O or N),giving rise to the 18-electron Ni(II)-H active species,[H1(Bpin)]and[H_(2)(Bpin)].Subtle tuning of the Ni-X pair and the supporting ancillary phosphine have a significant effect on the reactivity and catalytic performance of Cp*Ni(1,2-R_(2)PC_(6)H_(4)X).Unlike[H_(2)(Bpin)],the activation of HBpin in[H1(Bpin)]is reversible,which enables the Ni-O complex to be an effective cooperative catalyst in the hydroboration of N-heteroarenes,and as well as ketones and imines.
文摘Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective.In this respect,catalytic deoxygenative amide reduction has proven to be promising but challenging,as this approach necessitates selective C-O bond cleavage.Herein,we report the selective hydroboration of primary,secondary,and tertiary amides at room temperature catalyzed by an earth-abundant-metal catalyst,Zr-H,for accessing diverse amines.Various readily reducible functional groups,such as esters,alkynes,and alkenes,were well tolerated.Furthermore,the methodology was extended to the synthesis of bio-and drug-derived amines.Detailed mechanistic studies revealed a reaction pathway entailing aldehyde and amido complex formation via an unusual C-N bond cleavage-reformation process,followed by C-O bond cleavage.
基金Financial supports from the Key Project of Chinese National Programs for Fundamental Research and Development(No.2016YFA0602900)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Y093)+1 种基金the Natural Science Foundation of China(No.81873071)the Pearl River S&T Nova Program of Guangzhou(No.201906010059)are gratefully acknowledged。
文摘The trans-hydroboration of alkyne represents a challenging task in organic synthesis.Reported herein is an Et2 Zn promotedβ-trans hydroboration of ynamides by using N-heterocyclic carbene(NHC)-ligated borane as boryl source.The reaction leads to a stereoselective construction of enamides bearing a valuable boryl substituent.Both aromatic and aliphatic ynamides were applicable to the reaction.Synthetic transformation of the C-B bond in the product via Suzuki-Miyaura coupling provides a simple and stereospecific route to multi-substituted enamides.Mechanistic studies were conducted and the possible mechanism was discussed.
文摘The symmetrical diketone Ⅱ, which can be synthesized in gram scale using a well established method, was used as a starting material to prepare the 11α-methoxy ketomethylene Ⅵ. This is in continuation of our study aiming at the synthesis of multihydroxylated cephalostatin analogues, as for example cephalostatin 1Ⅰ, a potent anti-tumor natural product. Compound Ⅵ underwent chemo- and regioselective hydroboration reaction at only one of △14.15 double bonds furnishing compound Ⅸ as a major product in a fair yield.
基金financially supported by the Fundamental Research Funds for the Central Universities(No.2232018A3-04,No.2232018-02,and No.2232018G-043)the Program of Introducing Talents of Discipline to Universities(No.105-07-005735)
文摘In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric analysis,and energy-dispersive X-ray spectroscopy revealed that an Anderson-type POM,(NH4)4[CuMo6O18(OH)6]·5H2O was successfully immobilized on the sponge based on electrostatic interactions.Morphological analysis indicated that the POM-loaded sponge retained its porous structure and that the POM was homogeneously distributed on the sponge walls.The POM-loaded sponge exhibited excellent mechanical properties by recovering 79.9%of its original thickness following a 60%compression strain.The POM-loaded sponge was found to effectively catalyze the hydroboration of phenylacetylenes,yielding excellent conversion and regioselectivity of up to 96%and 99%,respectively.Its catalytic activity remained unchanged after five reuse cycles.These findings represent a scalable strategy for immobilizing POMs on porous supports.
基金supported by the National Natural Science Foundation of China(22271242,22071210,21933004)the Innovation and Technology Commission(ITC-CNERC14SC01)+2 种基金the Research Grants Council of Hong Kong(16309722,16304322,16309023)the Natural Science Foundation of Guangdong Province(2022A1515011859)the Key-Area Research and Development Program of Guangdong Province(2020B010188001).
文摘Organoboron compounds are highly versatile building blocks in modern organic synthesis,pharmaceuticals,and materials science,offering unique reactivity and stability for the assembly of complex molecular structures.The hydroboration of allenes stands out as a straightforward method for the preparation of allyl and alkenyl boranes.Nonetheless,achieving precise control over regio-and stereoselectivity in these reactions presents significant challenges.In this review,we have systematically summarized the selective hydroboration of allenes catalyzed by a range of transition metals,including platinum,copper,palladium,cobalt,nickel,and ruthenium catalysts.The significant advancements,current limitations,and future perspective for the transition metal-catalyzed selective hydroboration are also highlighted.Moreover,we hope that this review will help understand more about the catalytic hydroboration of allenes and stimulate the further development of both allene and organoboron chemistry.
基金the funding of the National Natural Science Foundation of China(22371269)the State Key Laboratory of Elementoorganic Chemistry Nankai University(202001)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0450301)the Open Project of Key Laboratory of Organosilicon Chemistry,and Material Technology of Ministry of Education,Hangzhou Normal University(KFJJ2022013)Anhui Provincial Major Science and Technology Project(2022e03020005).
文摘Arylidenecyclopropanes(ACPs)are highly strained substrates that can be readily utilized for diverse transformations.This study showcases the outcomes of copper-catalyzed ring-opening hydrosilylation and hydroboration reactions of ACPs,showcasing precise cleavage of C—C bonds.The reaction presents an effective and convenient method for producing homoallylic silanes and boronates.
基金the National Key R&D Program of China(grant no.2021YFF0701600)the National Natural Science Foundation of China(grant no.22225103)Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs,Shanghai Jiao Tong University,and the China Postdoctoral Science Foundation(grant nos.2020M680021 and 2021T140366),which was greatly appreciated.
文摘Selective reduction of readily available N-heteroarenes is important in both organic synthesis and chemical biology.Herein,we describe ligand-controlled regiodivergent hydroboration of quinolines using well-defined amido-manganese catalysts,with an emphasis on the rarely reported 1,4-regioselectivity.Mechanistic studies showed that 1,2-hydroboration of quinoline was kinetically favorable and reversible,whereas 1,4-hydroboration was under thermodynamic control.Using a 1-methyimidazolebased pincer amido-manganese complex as the catalyst,cooperative C-H…N andπ…πnoncovalent interactions between the 1-methyimidazole moiety and quinoline substrates enabled kinetic accessibility of 1,4-hydroboration,giving thermodynamically favored 1,4-hydroborated quinolines as the major products.On this basis,Mn-catalyzed 1,4-hydroboration of a series of substituted quinolines proceeded smoothly in high yields.A high turnover number of 2500 was achieved in this reaction with satisfying regioselectivity.This transformation could be further applied to the C3-selective functionalization of quinolines,highlighting the synthetic utility of this methodology.In contrast,using a pyridine-based pincer amido-manganese complex as the catalyst,which lacked the C-H…N interaction,the free-energy barrier for 1,4-hydroboration significantly increased through a N-B…N interaction between the“HMn-NB”species and quinoline,resulting in the kinetically favored 1,2-hydroboration product with excellent regioselectivity.
基金This work was supported by the National Key R&D Program of China(2018YFA0702003)the National Natural Science Foundation of China(21890383,21671117,21871159 and 21901135).
文摘The rational design of efficient single-atomic(SA)catalysts is essential and highly desirable but impeded by the lack of sufficient acknowledge between structure and property.To this end,it is critical to clarify the effect of the coordination structure of active metal centers on the catalytic activities for the design of such catalysts.Here,we report that different coordination structures of SA Pt catalysts can dramatically influence their activities for anti-Markovnikov hydroboration of alkenes.Compared with the other two coordination structures(Pt-N4 and Pt-O2),the SA Pt species coordinated with three O atoms(Pt-O3)display the highest turnover number value of 3288 for the hydroboration reaction to access the important alkylboronic esters.Density functional theory calculations reveal that a superior catalytic activity can be expected for alkene hydroboration over the three O coordinated Pt species due to the lowest reaction energy(ΔG)limiting step from the reaction phase diagram.
基金supported by the National Key R&D Program of China (2016YFA0202900, 2015CB856600)the National Natural Science Foundation of China (21825109, 21432011, 21572255, 21732006)+1 种基金Chinese Academy of Sciences (XDB20000000, QYZDB-SSWSLH016)Science and Technology Commission Shanghai Municipality (17JC1401200)
文摘Regiodivergent 1,2-hydroboration of 1,3-dienes with pinacolborane has been accomplished by well-defined cobalt complexes of different bidentate ligands. The iminopyridine-cobalt system is selective for Markovnikov 1,2-hydroboration to form allylboronates, while the FOXAP-cobalt(FOXAP=(S)-1-(diphenylphosphino)-2-[(S)-4-isopropyloxazolin-2-yl]ferrocene) catalyst effects the complementary anti-Markonikv 1,2-hydroboration to afford homoallyboronates with high regioselectivity.
基金the financial support from the National Natural Science Foundation of China(Nos.21871269 and 21521002).
文摘Main observation and conclusion In this work,a novel mode for the activation of N-heterocyclic carbene boranes(NHC-boranes)was developed by generating the highly reactive zwitterion species through hydride abstraction with Lewis acid B(C_(6)F_(5))_(3) in an frustrated Lewis pairs manner.A broad range of alkenes including stilbenes,β-methylstyrenes,styrenes,and alkyl-alkenes were suitable substrates for the B(C_(6)F_(5))_(3)-catalyzed hydroboration to furnish the desired products in good to high yields.Significantly,excellent regioselectivities were obtained in some cases.Mechanistic studies indicate that the B-H bond cleavage is likely involved in the rate-determining step.In addition,an electrophilic addition of NHC-borenium cation to alkenes and the subsequent formation of carbocation are also postulated.The current work provides a promising method for the activation of stable borane adducts,which might lead to some interesting transformations in the future.
文摘We have previously reported that the Ti complex generated from Cp2TiCl2 and LiBH4 serves as a catalyst for hydroboration of alkenes. Sodium borohydride can also be utilized as a reagent for hydroboration if reaction is carried out in the pre-
基金supported by the National Natural Science Foundation of China(Grant No.91961116)the Fundamental Research Funds for the Central Universities,and Programs for high-level entrepreneurial and innovative talents introduction of Jiangsu Province。
文摘The strong oxophilicity of actinide complexes prevents their applications in the transformation of oxygen-containing substrates.Herein,we report the use of a uranium(Ⅳ)alkyl complex as a catalyst for the hydroboration of carbonyl compounds.This reaction has good functional group tolerance and chemo-selectivity under mild conditions.This study represents the rare example of catalytic reaction promoted by a uranium alkyl complex and highlights the potential of uranium complexes in synthetic chemistry.
基金The authors acknowledge financial support from the National Natural Science Foundation of China(No.21821002).
文摘The sustainable development of synthetic reactions catalyzed by earth-abundant metals is one of the principal goals in homogeneous catalysis.However,so far most of the protocols are still plagued by sophisticated ligands,hazardous activators,high catalyst loading(1—10 mol%)and/or multistep synthesis of the metal complexes in the process development.Consequently,the development of earth-abundant metal catalysts with high activity from commercially available metal salts is highly desirable for practical utilization of base metal catalyzed synthetic methodology.Herein,we report the catalyst generated in situ from a mixture of catalytic amounts of Ni(acac)_(2)(as low as 0.005 mol%)and CsF,which is found highly active for Markovnikov-selective hydroboration of vinylarenes,including 1,1-disubstituted vinylarenes and internal olefins,affording a wide range of secondary and tertiary alkyl boronates in excellent yields.Mechanistic experiments indicate that the key to the success of this catalysis is the use of CsF,which in combination with pinacolborane acts as an effective activator for Ni(acac)_(2),probably generating metastable Ni nanoparticles in situ that demonstrate high activity in the catalytic hydroboration(TON up to 18800).
基金support obtained from the Chinese Academy of Sciences(QYZDY-SSWSLH026 and XDB20020000)and the Drug Innovation Major Project(2018ZX09711001-005)is highly appreciated.The authors thank Zuming Lin for assisting with the experiments and Dr.Xiaoli Bao(SJTU)and Jie Sun(SIOC)for performing the X-ray analysis.
文摘Polyketides,a large class of secondary metabolites,have been of long-standing interest to the synthetic community due to their intriguing biological activities and structural versatility and complexity.A typical structural unit of various natural products,polypropionate,has prompted enormous efforts in the development of novel synthetic methods and strategies in the past five decades.In this study,a non-aldol-type approach based on double hydroboration of allenes has been developed to provide a powerful method for the stereodivergent construction of various polyol stereotriads and stereotetrads that are amenable for synthesizing polypropionates.The stereochemical control is possibly attributable to the boronate complex that aligned itself as a rigid conformation for the second stereoselective hydroboration reaction by suppressing the barotropic rearrangement of allylborane intermediates.The feasibility of preparing the key polypropionate motif facilitates the efficient synthesis of(-)-pironetin,a potentα-tubulin inhibitor halting the cell cycle at M phase.
基金financial support from the "1000 Youth Talents Plan"the National Natural Science Foundation of China (Nos. 21402107, 91427303)the Natural Science Foundation of Shandong Province (Nos. ZR2014M011)
文摘A new class of iron（II） hydrides based on a tetradentate PSNP ligand were synthesized and fully characterized. All the iron（II） complexes feature a folded PSNP ligand with cis reactive sites. The hydrido iron complex [2 H（NCMe[2_TD$IF]1）]（BF4） is capable of catalyzing aldehyde hydroboration by pinacolborane（HBpin） and with extremely high efficiency at room temperature. Aldehydes with various functional groups are compatible.
