Borylative cyclization of E-3-arylallyl carbamoyl chlorides is achieved through copper catalyzed intramolecular carboboration with B_(2)pin_(2).2-Aryl-3-boryl-γ-lactams are formed with exclusive cisdiastereoselectivi...Borylative cyclization of E-3-arylallyl carbamoyl chlorides is achieved through copper catalyzed intramolecular carboboration with B_(2)pin_(2).2-Aryl-3-boryl-γ-lactams are formed with exclusive cisdiastereoselectivity.CuBr-Dppp combination gives the best outcomes.The substrate scope is profiled.展开更多
Alicyclic nitrogen heterocycles,such as enantioenriched polycyclic fused[1,2-a]indoline derivatives,are widespread in natural products,agrochemicals and pharmaceutical agents.Existing methods predominantly rely on the...Alicyclic nitrogen heterocycles,such as enantioenriched polycyclic fused[1,2-a]indoline derivatives,are widespread in natural products,agrochemicals and pharmaceutical agents.Existing methods predominantly rely on the recent emerging Heck-type catalytic asymmetric dearomatization(CADA)protocol,wherein noble palladium catalysts commonly necessitate the form arylPd species-triggered these transformations.In contrast,a more sustainable base metal catalysis paradigm through alkyl metal species disrupting the aromaticity,that is,the utilization of challenging asymmetric Csp3–Csp3 bond formation entry to such important chiral densely functionalized polycyclic molecular scaffolds,remains an elusive task.Herein,we report the first copper-catalyzed dearomative borylative cyclization of indoles under mild reaction conditions,affording an array of valuable Bpin-containing pyrrolo-fused[1,2-a]indolines bearing four consecutive stereogenic centers with excellent enantioand diastereoselectivity.The synthetic potential was documented via an array of useful transformations.Density functional theory(DFT)calculation studies elucidated the origin of the chemo-,regio-,enantio-and diastereoselectivities of this conversion.展开更多
Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excell...Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excellent yields with good functionality compatibility.In addition,the gram-scale synthesis and the application of the approach in the late-stage elaboration of aryl nonaflate derived from pterostilbene could also be achieved.展开更多
Azaarenes are attractive structural units widely found in chiral pharmaceuticals,agrochemicals,and biologically active natural products.An ongoing strategy has been the construction of new chiral molecules containing ...Azaarenes are attractive structural units widely found in chiral pharmaceuticals,agrochemicals,and biologically active natural products.An ongoing strategy has been the construction of new chiral molecules containing azaarenes by virtue of the electron-deficient properties of azaarenes.Herein,an asymmetric three-component coupling of vinylazaarenes,B2Pin2,and ketones was achieved in the presence of a chiral copper(I)catalyst.The reaction favored a broad substrate scope of either vinylazaarenes or ketones.High enantioselectivity was observed in this reaction together with moderate diastereoselectivity,attributable to the relatively small difference of steric repulsion between two proposed transition states.Finally,the synthetic utilities of the product were demonstrated by several beneficial transformation reactions.展开更多
Vicinal stereogenic centers are ubiquitous structural scaffolds in both natural products and synthetic compounds,yet their enantioselective construction remains a significant challenge in organic synthesis.Organoboron...Vicinal stereogenic centers are ubiquitous structural scaffolds in both natural products and synthetic compounds,yet their enantioselective construction remains a significant challenge in organic synthesis.Organoboron compounds are of paramount importance in synthetic chemistry due to their ability to undergo facile transformations,yielding diverse essential chemical bonds such as carbon-carbon,carbon-oxygen,carbon-nitrogen,and carbon-halogen bonds.Transition-metal-catalyzed asymmetric borylative functionalizations of internal alkenes offer a promising strategy for the enantioselective installation of two adjacent chiral centers across carbon-carbon bonds.By leveraging the versatile transformations of the newly introduced boryl unit,this approach holds great potential for expanding the structural diversity of vicinal stereogenic scaffolds.In this concise review,we aim to highlight recent advancements in transition-metal-catalyzed asymmetric borylative functionalizations of internal alkenes,underscore their utility as a versatile approach for constructing vicinal stereogenic centers,and discuss unsolved challenges and future directions in this field.展开更多
A metal-free,visible-light-induced strategy has been developed for the diborylation of gem-dibromoalkanes.This reaction enables the construction of structurally diverse alkyl gem-diboronates at room temperature via vi...A metal-free,visible-light-induced strategy has been developed for the diborylation of gem-dibromoalkanes.This reaction enables the construction of structurally diverse alkyl gem-diboronates at room temperature via visible-light-induced C—Br bond activation using B2cat2 as the boron source.Through a tandem in-situ dibromination/diborylation process,a onepot transformation from aldehydes to alkyl gem-diboronates has been achieved.Additionally,sunlight irradiation has been demonstrated as a viable alternative for inducing this reaction,enabling gram-scale synthesis with practical applicability.展开更多
Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron...Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products.展开更多
Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,th...Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,the catalysts employed in homogeneous catalysis are generally expensive,sensitive,and difficult to separate from the reaction mixture and reuse.With the rapid development of heterogeneous catalysis,heterogeneous C-H and C-X borylation have emerged as highly efficient and sustainable approaches towards the synthesis of organoboron compounds.This review aims to highlight the recent advances in the synthesis of organoboron compounds employing heterogeneous C-H and C-X borylation strategies.We endeavor to shed light on new perspectives and inspire further research and applications in this emerging area.展开更多
Metal hydrides serve as crucial intermediates in many chemical processes,facilitating the utilization of hydrogen resources.Traditionally,three-centre metal hydrides have been viewed as less reactive due to their mult...Metal hydrides serve as crucial intermediates in many chemical processes,facilitating the utilization of hydrogen resources.Traditionally,three-centre metal hydrides have been viewed as less reactive due to their multi-stabilization effects.However,recent discoveries show the"three-centre four-electron"(3c-4e)bridging hydride bond exhibits significant activity in boryl transition metal systems.This research employs computational techniques to explore the factors that influence the formation of the 3c-4e bridging hydride,focusing on boryl 3d non-noble transition metals ranging from chromium(Cr)to nickel(Ni).By analyzing bond distances and bond orders,the study sheds light on the electronic and structural characteristics of the B-H-M bridging hydride.It reveals a clear link between the metal centre’s redox properties and the emergence of bridging hydrides.Specifically,metal centres like Cr and Co,which have lower oxidation states and electronegativity,are more inclined to form active 3c-4e bridging hydrides.These insights,derived from computational analyses,offer valuable guidelines for the development of active 3c-4e bridging metal hydrides,thereby contributing to the advancement of new hydrogen transformation catalysts.展开更多
Geminal diboronates and diarylmethyl boronates are versatile building blocks in synthetic chemistry.We here reported a highly efficient approach for the synthesis of gem-bisborylalkanes and diarylmethyl boronates via ...Geminal diboronates and diarylmethyl boronates are versatile building blocks in synthetic chemistry.We here reported a highly efficient approach for the synthesis of gem-bisborylalkanes and diarylmethyl boronates via cobalt-catalyzed deoxygenative borylation of diaryl ketones.This borylation protocol is compatible with a broad range of functionalized aryl groups,providing access to a wide array of boronic esters.The resulting boronic esters can be further transformed to various cross-coupling products and TPEs that represent important structural motifs in organic chemistry and materials science.展开更多
Metal-free heterogeneous photocatalysts provide an environmental-friendly and cost-efficient avenue for green organic synthesis.Covalent organic frameworks(COFs)as heterogeneous photocatalysts showcase promising poten...Metal-free heterogeneous photocatalysts provide an environmental-friendly and cost-efficient avenue for green organic synthesis.Covalent organic frameworks(COFs)as heterogeneous photocatalysts showcase promising potential in the field of photocatalytic organic reactions due to their high porosity,insolubility and tailor-made functions.However,thus far,COF-based catalysts only mediated a few types of reactions.Herein,we developed a series of isoreticular nitrogen-rich covalent organic frameworks(N-COFs)with comparable porous structures as photocatalysts which effectively mediated the borylation of aryl iodides with broad substrate scope.Remarkably,6N-COF exhibits excellent photocatalytic efficiency and superior recyclability.It suggests a new pathway to construct efficient heterogeneous photocatalysts for the borylation of aryl halides.展开更多
Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be challenging.He...Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be challenging.Herein,a copper-catalyzed chemo-,regio-,and stereo-selective diborylation of 1,3-enynes for the efficient construction of 1,4-diborylated allenes under base-free conditions was reported.A wide range of 1,3-enynes bearing various functional groups can participant in the reaction and afforded the corresponding 1,4-diborylated allenes in good to excellent yields,which was enabled by the protocol of Bpin to BF3K conversion.the borylcopper species was supposed to selectively attack the C-C triple bond of the 1,3-enynes.展开更多
An electrochemically promoted decarboxylative borylation reaction is reported. The reaction proceeds under mild conditions in an undivided cell without use of transition metal-or photo-catalysts. The key feature of th...An electrochemically promoted decarboxylative borylation reaction is reported. The reaction proceeds under mild conditions in an undivided cell without use of transition metal-or photo-catalysts. The key feature of the reaction is the compatibility of diboron reagents with the electrochemical conditions. This reaction exhibits broad substrate scope, good functional group tolerability, and easy scalability.展开更多
The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We...The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We discover that a non-directed pathway,in which the urea moiety in ligand recognizes the O atom in Bpin instead of substrate,competes with the directed pathway and erodes the meta-selectivity.The non-directed pathway is sensitive to steric repulsion between Bpin and urea,and thus can be impeded by introducing a bulky substituent into the urea moiety.Accordingly,we optimize the ligand and improve the meta-selectivity in the Ir-catalyzed C-H borylation of some previously reported unsuccessful arenes.展开更多
A cooperative Pd/Cu-catalyzed three-component cross-coupling reaction of alkynes,B_(2)Pin_(2) and alkene-tethered aryl halides is reported.This reaction proceeds under mild conditions and shows broad sub-strate scope,...A cooperative Pd/Cu-catalyzed three-component cross-coupling reaction of alkynes,B_(2)Pin_(2) and alkene-tethered aryl halides is reported.This reaction proceeds under mild conditions and shows broad sub-strate scope,providing a variety of heterocycles containing tetrasubstituted alkenylboronate moieties in synthetically useful yields with excellent chemoselectivity and regioselectivity.This transformation fea-tures the catalytic generation ofβ-borylalkenylcopper intermediates and their use in Pd-catalyzed Heck cyclization/cross-couplings.An enantioselective cascade cyclization/cross-coupling process has also been developed for the synthesis of enantiomerically enriched oxindole bearing a tetrasubstituted alkenyl-boronate moiety.展开更多
A novel method for metal-free C-H borylation of 2-(N-methylanilino)-5-fluoropyridines and 2-benzyl-5-fluoropyridines has been reported. The 5-fluoropyridine directed borylation reaction exhibited high efficiency and s...A novel method for metal-free C-H borylation of 2-(N-methylanilino)-5-fluoropyridines and 2-benzyl-5-fluoropyridines has been reported. The 5-fluoropyridine directed borylation reaction exhibited high efficiency and site exclusivity. The useful protocol could be executed on a gram-scale easily and the borylated products showed good derivatization applications. Moreover, the practicality of the strategy was expanded by the fact that the directing group could be removed in an acceptable yield.展开更多
A(POCOP)-supported palladium complex was used to catalyse the dehydrogenative borylation of terminal alkynes to form alkynylboronates.Competing hydrogenation reactions could be mitigated through the use of additives s...A(POCOP)-supported palladium complex was used to catalyse the dehydrogenative borylation of terminal alkynes to form alkynylboronates.Competing hydrogenation reactions could be mitigated through the use of additives such as phosphines or elemental mercury.展开更多
Over the last decade,boron-based complexes have been emerging as unique catalysts for the bifunctional activation of small molecules.To reveal the difference in the electronic regulatory factors on the design of elect...Over the last decade,boron-based complexes have been emerging as unique catalysts for the bifunctional activation of small molecules.To reveal the difference in the electronic regulatory factors on the design of electrophilic borane and nucleophilic boryl transition metal catalysts,the DPB-Ni complex was selected as a representative catalyst to investigate their performance in H_(2)activation using density functional theory(DFT)calculations.Our findings reveal that the nucleophilic sp^(3)boryl-nickel catalyst had a higher activity than the electrophilic borane-nickel catalyst for H_(2)activation.The Lewis basicity of boryl could be enhanced by the dative pyridine group,increasing the activity of the boryl-nickel catalyst.In the electrophilic sp^(3)borane-nickel system,the electron-withdrawing group(EWG)enhanced the M→B dative bond,suppressing the cleavage of the B-Ni bond during the H_(2)activation,while the formation of the B-H-Ni bond was facilitated by the EWG group.The electron-donating group(EDG)resulted in similar influences.These compromised results surprisingly led to an insignificant electronic effect on the activity.In the nucleophilic sp^(3)boryl-nickel system,the electronic effect of the ligands significantly influenced the catalytic performance.The EDG increased the nucleophilicity of the boryl to assist H_(2)activation and enhanced the electron density of the metal center for H_(2)oxidative addition,significantly improving the activity;whereas,the EWG group decreased the reaction activity.The distinct electronic effect revealed by this study will be helpful to advance the rational design of boron-based transition metal catalysts for bifunctional catalysis and their applications.展开更多
The first examples of NHC-supported borylnickel complexes have been accessed via the reaction of a phosphine-tethered carbene-bromoborane adduct and a Ni(0)source.DFT calculations and Ni K-and L-edge XANES data indica...The first examples of NHC-supported borylnickel complexes have been accessed via the reaction of a phosphine-tethered carbene-bromoborane adduct and a Ni(0)source.DFT calculations and Ni K-and L-edge XANES data indicate that there is significant Ni(0)character in the resulting complexes,and that the boryl ligand in this case is best regarded as a Z-type acceptor ligand.Reactivity studies of this novel complex have found an unprecedented insertion product with an aryl isocyanide forming an 8-membered metallocycle,and a Ni abnormal-carbene complex has also been accessed from an analogous reaction with a chloroborane precursor.展开更多
Organoboron compounds have garnered significant attention in the fields of organic synthesis,materials science,medicinal chemistry and fine chemicals.In the past few decades,transition metal-catalyzed C–H borylation ...Organoboron compounds have garnered significant attention in the fields of organic synthesis,materials science,medicinal chemistry and fine chemicals.In the past few decades,transition metal-catalyzed C–H borylation has been developed rapidly and efficiently.In recent years,in order to explore eco-friendly,economical and efficient method for constructing C–B bond,chemists are dedicated to developing metalfree BX_(3)-mediated borylation.In this review,we present a systematic and comprehensive overview of the borylation driven by BX_(3) with different directing group auxiliary in the fields of organic synthesis and boron-containing organic materials since 2010,including(1)nitrogen directed C–H borylation,(2)oxygen directed C–H borylation,(3)sulfur directed C–H borylation and(4)phosphorus directed C–H borylation.The methods of borylation processes as well as the substance scopes,limits,and mechanisms of these routes are also discussed.展开更多
基金the National Natural Science Foundation of China(No.21672027)for financial supportsupported by High-Level Entrepreneurial Talent Team of Jiangsu Province(No.2017-37)。
文摘Borylative cyclization of E-3-arylallyl carbamoyl chlorides is achieved through copper catalyzed intramolecular carboboration with B_(2)pin_(2).2-Aryl-3-boryl-γ-lactams are formed with exclusive cisdiastereoselectivity.CuBr-Dppp combination gives the best outcomes.The substrate scope is profiled.
基金supported by the Natural Science Foundation of Jilin Province(20210101134JC)the National Natural Science Foundation of China(22171042,21831002,22193012)the Fundamental Research Funds for the Central Universities.
文摘Alicyclic nitrogen heterocycles,such as enantioenriched polycyclic fused[1,2-a]indoline derivatives,are widespread in natural products,agrochemicals and pharmaceutical agents.Existing methods predominantly rely on the recent emerging Heck-type catalytic asymmetric dearomatization(CADA)protocol,wherein noble palladium catalysts commonly necessitate the form arylPd species-triggered these transformations.In contrast,a more sustainable base metal catalysis paradigm through alkyl metal species disrupting the aromaticity,that is,the utilization of challenging asymmetric Csp3–Csp3 bond formation entry to such important chiral densely functionalized polycyclic molecular scaffolds,remains an elusive task.Herein,we report the first copper-catalyzed dearomative borylative cyclization of indoles under mild reaction conditions,affording an array of valuable Bpin-containing pyrrolo-fused[1,2-a]indolines bearing four consecutive stereogenic centers with excellent enantioand diastereoselectivity.The synthetic potential was documented via an array of useful transformations.Density functional theory(DFT)calculation studies elucidated the origin of the chemo-,regio-,enantio-and diastereoselectivities of this conversion.
文摘Nickel-catalyzed borylation of aryl nonaflates with B2pin2 could be realized,which proceeded effectively by means of C—O bond functionalization to afford a wide variety of valuable arylboronates in moderate to excellent yields with good functionality compatibility.In addition,the gram-scale synthesis and the application of the approach in the late-stage elaboration of aryl nonaflate derived from pterostilbene could also be achieved.
基金the National Natural Science Foundation of China(grant nos.21672235,21871287,and 21922114)the financial support from the“Thousand Youth Talents Plan,”the Strategic Priority Research Program of the Chinese Academy of Sciences(no.XDB20000000)CAS Key Laboratory of Synthetic Chemistry of Natural Substances,and Shanghai Institute of Organic Chemistry.
文摘Azaarenes are attractive structural units widely found in chiral pharmaceuticals,agrochemicals,and biologically active natural products.An ongoing strategy has been the construction of new chiral molecules containing azaarenes by virtue of the electron-deficient properties of azaarenes.Herein,an asymmetric three-component coupling of vinylazaarenes,B2Pin2,and ketones was achieved in the presence of a chiral copper(I)catalyst.The reaction favored a broad substrate scope of either vinylazaarenes or ketones.High enantioselectivity was observed in this reaction together with moderate diastereoselectivity,attributable to the relatively small difference of steric repulsion between two proposed transition states.Finally,the synthetic utilities of the product were demonstrated by several beneficial transformation reactions.
基金National Natural Science Foundation of China(22271161,22188101)the Tianjin Science Fund for Distinguished Young Scholars(23JCJQJC00180)+1 种基金the Fundamental Research Funds for the Central Universities(63233165,63243134)Nankai University,for financial support.
文摘Vicinal stereogenic centers are ubiquitous structural scaffolds in both natural products and synthetic compounds,yet their enantioselective construction remains a significant challenge in organic synthesis.Organoboron compounds are of paramount importance in synthetic chemistry due to their ability to undergo facile transformations,yielding diverse essential chemical bonds such as carbon-carbon,carbon-oxygen,carbon-nitrogen,and carbon-halogen bonds.Transition-metal-catalyzed asymmetric borylative functionalizations of internal alkenes offer a promising strategy for the enantioselective installation of two adjacent chiral centers across carbon-carbon bonds.By leveraging the versatile transformations of the newly introduced boryl unit,this approach holds great potential for expanding the structural diversity of vicinal stereogenic scaffolds.In this concise review,we aim to highlight recent advancements in transition-metal-catalyzed asymmetric borylative functionalizations of internal alkenes,underscore their utility as a versatile approach for constructing vicinal stereogenic centers,and discuss unsolved challenges and future directions in this field.
文摘A metal-free,visible-light-induced strategy has been developed for the diborylation of gem-dibromoalkanes.This reaction enables the construction of structurally diverse alkyl gem-diboronates at room temperature via visible-light-induced C—Br bond activation using B2cat2 as the boron source.Through a tandem in-situ dibromination/diborylation process,a onepot transformation from aldehydes to alkyl gem-diboronates has been achieved.Additionally,sunlight irradiation has been demonstrated as a viable alternative for inducing this reaction,enabling gram-scale synthesis with practical applicability.
文摘Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products.
基金supported by grants from the National Natural Science Foundation of China(Nos.22271313,21602096)the Fund for Academic Innovation Teams of South-Central Minzu University(No.XTZ24015)South-Central Minzu University.
文摘Homogeneous C-H and C-X borylation via transition-metal-catalysis have undergone rapid development in the past decades and become one of the most practical methods for the synthesis of organoboron compounds.However,the catalysts employed in homogeneous catalysis are generally expensive,sensitive,and difficult to separate from the reaction mixture and reuse.With the rapid development of heterogeneous catalysis,heterogeneous C-H and C-X borylation have emerged as highly efficient and sustainable approaches towards the synthesis of organoboron compounds.This review aims to highlight the recent advances in the synthesis of organoboron compounds employing heterogeneous C-H and C-X borylation strategies.We endeavor to shed light on new perspectives and inspire further research and applications in this emerging area.
基金supported by the National Natural Science Foundation of Chian(NSFC,Nos.22373118 and 22231002)the Guangdong Basic and Applied Basic Research Foundation(No.2024B1515040025)the Fundamental Research Funds for the Central Universities.
文摘Metal hydrides serve as crucial intermediates in many chemical processes,facilitating the utilization of hydrogen resources.Traditionally,three-centre metal hydrides have been viewed as less reactive due to their multi-stabilization effects.However,recent discoveries show the"three-centre four-electron"(3c-4e)bridging hydride bond exhibits significant activity in boryl transition metal systems.This research employs computational techniques to explore the factors that influence the formation of the 3c-4e bridging hydride,focusing on boryl 3d non-noble transition metals ranging from chromium(Cr)to nickel(Ni).By analyzing bond distances and bond orders,the study sheds light on the electronic and structural characteristics of the B-H-M bridging hydride.It reveals a clear link between the metal centre’s redox properties and the emergence of bridging hydrides.Specifically,metal centres like Cr and Co,which have lower oxidation states and electronegativity,are more inclined to form active 3c-4e bridging hydrides.These insights,derived from computational analyses,offer valuable guidelines for the development of active 3c-4e bridging metal hydrides,thereby contributing to the advancement of new hydrogen transformation catalysts.
基金financial support from the National Natural Science Foundation of China(Nos.22271086 and 21971059)the National Program for Thousand Young Talents of Chinathe Fundamental Research Funds for the Central Universities。
文摘Geminal diboronates and diarylmethyl boronates are versatile building blocks in synthetic chemistry.We here reported a highly efficient approach for the synthesis of gem-bisborylalkanes and diarylmethyl boronates via cobalt-catalyzed deoxygenative borylation of diaryl ketones.This borylation protocol is compatible with a broad range of functionalized aryl groups,providing access to a wide array of boronic esters.The resulting boronic esters can be further transformed to various cross-coupling products and TPEs that represent important structural motifs in organic chemistry and materials science.
基金financially supported by National Natural Science Foundation of China(No.51973153)。
文摘Metal-free heterogeneous photocatalysts provide an environmental-friendly and cost-efficient avenue for green organic synthesis.Covalent organic frameworks(COFs)as heterogeneous photocatalysts showcase promising potential in the field of photocatalytic organic reactions due to their high porosity,insolubility and tailor-made functions.However,thus far,COF-based catalysts only mediated a few types of reactions.Herein,we developed a series of isoreticular nitrogen-rich covalent organic frameworks(N-COFs)with comparable porous structures as photocatalysts which effectively mediated the borylation of aryl iodides with broad substrate scope.Remarkably,6N-COF exhibits excellent photocatalytic efficiency and superior recyclability.It suggests a new pathway to construct efficient heterogeneous photocatalysts for the borylation of aryl halides.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.22001251,21922112,and 22225107)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20000000)+1 种基金National Key R&D Program of China(No.2017YFA0700103)the Guizhou Provincial S&T Project(No.2018[4007]).
文摘Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be challenging.Herein,a copper-catalyzed chemo-,regio-,and stereo-selective diborylation of 1,3-enynes for the efficient construction of 1,4-diborylated allenes under base-free conditions was reported.A wide range of 1,3-enynes bearing various functional groups can participant in the reaction and afforded the corresponding 1,4-diborylated allenes in good to excellent yields,which was enabled by the protocol of Bpin to BF3K conversion.the borylcopper species was supposed to selectively attack the C-C triple bond of the 1,3-enynes.
基金supported by the National Natural Science Foundation of China (Nos. 21871074 and 21971051)the National Key R&D Program of China (No. 2018YFB1501604)+1 种基金the Fundamental Research Funds for the Central Universities (No. PA2020GDKC0021)the Key Research and Development Program Projects in Anhui Province (No. 201904a07020069)。
文摘An electrochemically promoted decarboxylative borylation reaction is reported. The reaction proceeds under mild conditions in an undivided cell without use of transition metal-or photo-catalysts. The key feature of the reaction is the compatibility of diboron reagents with the electrochemical conditions. This reaction exhibits broad substrate scope, good functional group tolerability, and easy scalability.
基金financial support from the Fundamental Research Funds for the Central Universities(Nos.020514380253,020514380277)the Natural Science Foundation of Jiangsu Province(No.BK20211555)the Jiangsu Innovation&Entrepreneurship Talents Plan。
文摘The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We discover that a non-directed pathway,in which the urea moiety in ligand recognizes the O atom in Bpin instead of substrate,competes with the directed pathway and erodes the meta-selectivity.The non-directed pathway is sensitive to steric repulsion between Bpin and urea,and thus can be impeded by introducing a bulky substituent into the urea moiety.Accordingly,we optimize the ligand and improve the meta-selectivity in the Ir-catalyzed C-H borylation of some previously reported unsuccessful arenes.
基金financial support from the National Natural Science Foundation of China(No.22171215)the Excellent Youth Foundation of Hubei Scientific Committee(No.2022CFA092)the GuangDong Basic and Applied Basic Research Foundation(No.2022A1515110113).
文摘A cooperative Pd/Cu-catalyzed three-component cross-coupling reaction of alkynes,B_(2)Pin_(2) and alkene-tethered aryl halides is reported.This reaction proceeds under mild conditions and shows broad sub-strate scope,providing a variety of heterocycles containing tetrasubstituted alkenylboronate moieties in synthetically useful yields with excellent chemoselectivity and regioselectivity.This transformation fea-tures the catalytic generation ofβ-borylalkenylcopper intermediates and their use in Pd-catalyzed Heck cyclization/cross-couplings.An enantioselective cascade cyclization/cross-coupling process has also been developed for the synthesis of enantiomerically enriched oxindole bearing a tetrasubstituted alkenyl-boronate moiety.
基金National Natural Science Foundation of China (No. 21676088) for financial support。
文摘A novel method for metal-free C-H borylation of 2-(N-methylanilino)-5-fluoropyridines and 2-benzyl-5-fluoropyridines has been reported. The 5-fluoropyridine directed borylation reaction exhibited high efficiency and site exclusivity. The useful protocol could be executed on a gram-scale easily and the borylated products showed good derivatization applications. Moreover, the practicality of the strategy was expanded by the fact that the directing group could be removed in an acceptable yield.
基金the US National Science Foundation(grant CHE-1300299 to O.V.O.)the Welch Foundation(grant A-1717 to O.V.O.).
文摘A(POCOP)-supported palladium complex was used to catalyse the dehydrogenative borylation of terminal alkynes to form alkynylboronates.Competing hydrogenation reactions could be mitigated through the use of additives such as phosphines or elemental mercury.
基金supported by the NSFC(no.21973113,22373118,and 22231002)the Guangdong Province Funds(no.2022SPT120208)the Fundamental Research Funds for the Central Universities.
文摘Over the last decade,boron-based complexes have been emerging as unique catalysts for the bifunctional activation of small molecules.To reveal the difference in the electronic regulatory factors on the design of electrophilic borane and nucleophilic boryl transition metal catalysts,the DPB-Ni complex was selected as a representative catalyst to investigate their performance in H_(2)activation using density functional theory(DFT)calculations.Our findings reveal that the nucleophilic sp^(3)boryl-nickel catalyst had a higher activity than the electrophilic borane-nickel catalyst for H_(2)activation.The Lewis basicity of boryl could be enhanced by the dative pyridine group,increasing the activity of the boryl-nickel catalyst.In the electrophilic sp^(3)borane-nickel system,the electron-withdrawing group(EWG)enhanced the M→B dative bond,suppressing the cleavage of the B-Ni bond during the H_(2)activation,while the formation of the B-H-Ni bond was facilitated by the EWG group.The electron-donating group(EDG)resulted in similar influences.These compromised results surprisingly led to an insignificant electronic effect on the activity.In the nucleophilic sp^(3)boryl-nickel system,the electronic effect of the ligands significantly influenced the catalytic performance.The EDG increased the nucleophilicity of the boryl to assist H_(2)activation and enhanced the electron density of the metal center for H_(2)oxidative addition,significantly improving the activity;whereas,the EWG group decreased the reaction activity.The distinct electronic effect revealed by this study will be helpful to advance the rational design of boron-based transition metal catalysts for bifunctional catalysis and their applications.
基金NSERC Discovery Grant RGPIN-2021-03056 and CFI JELF/BCKDF 41570 for fundingsupported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences under Contract No.DE-AC02-76SF00515.
文摘The first examples of NHC-supported borylnickel complexes have been accessed via the reaction of a phosphine-tethered carbene-bromoborane adduct and a Ni(0)source.DFT calculations and Ni K-and L-edge XANES data indicate that there is significant Ni(0)character in the resulting complexes,and that the boryl ligand in this case is best regarded as a Z-type acceptor ligand.Reactivity studies of this novel complex have found an unprecedented insertion product with an aryl isocyanide forming an 8-membered metallocycle,and a Ni abnormal-carbene complex has also been accessed from an analogous reaction with a chloroborane precursor.
基金Early-Career Young Scientists and Technologists Project of Jiangxi Province(No.20244BCE52224)Jiangxi Provincial Natural Science Foundation(No.20252BAC200240)+1 种基金the Start-up Funds of Gannan Medical University(No.QD202406)National Key R&D Program of China(No.2023YFC3504100)for financial support。
文摘Organoboron compounds have garnered significant attention in the fields of organic synthesis,materials science,medicinal chemistry and fine chemicals.In the past few decades,transition metal-catalyzed C–H borylation has been developed rapidly and efficiently.In recent years,in order to explore eco-friendly,economical and efficient method for constructing C–B bond,chemists are dedicated to developing metalfree BX_(3)-mediated borylation.In this review,we present a systematic and comprehensive overview of the borylation driven by BX_(3) with different directing group auxiliary in the fields of organic synthesis and boron-containing organic materials since 2010,including(1)nitrogen directed C–H borylation,(2)oxygen directed C–H borylation,(3)sulfur directed C–H borylation and(4)phosphorus directed C–H borylation.The methods of borylation processes as well as the substance scopes,limits,and mechanisms of these routes are also discussed.
