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
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
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
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
The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials.Facile,...The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials.Facile,selective,and programmable routes to helicenes or heterohelicenes are highly desirable yet challenging for structure-chiroptical property relationship studies.Herein,we report the synthesis and characterization of NBN-doped helicenes with boron atoms in the inner rims,enabled by the highly regioselective one-pot borylation of rationally designed precursors with,namely,fold-in or pan-out manner.The incorporation of nonbonded boron and nitrogen atoms resulted in narrow-band emission and improved optical properties for the single-stranded carbon helix.In addition,numbers and arrangement modes of fused six-membered rings have distinct effects on configurational stability and chiroptical properties,revealing that BN-[6]H with strong circular dichroism is a promising candidate for chiral sensors.The combination of experimental and theoretical studies on these helical structures might provide insights into the design of helically chiral small-molecule-based sensors or emitters.展开更多
A simple electrochemically mediated method for the conversion of nitroarenes to aryl boronic esters is presented.Electrochemical borylation of a diverse range of nitroarenes,including the late-stage borylation of bioa...A simple electrochemically mediated method for the conversion of nitroarenes to aryl boronic esters is presented.Electrochemical borylation of a diverse range of nitroarenes,including the late-stage borylation of bioactive molecules,is furnished at room temperature under simple conditions,thereby demonstrating the broad utility and functional-group tolerance of this protocol.This transformation provides a convenient and practical access to aryl boronic esters from widely available nitroarenes,which would significantly streamline the synthetic process of diverse functionalized arenes.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
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
We describe an iridium-catalyzed ortho-selective C–H borylation of unprotected anilines.The employing strongσ-donating cyclometalated mesoionic carbene as C^C bidentate ligand is crucial for the high ortho-selectivi...We describe an iridium-catalyzed ortho-selective C–H borylation of unprotected anilines.The employing strongσ-donating cyclometalated mesoionic carbene as C^C bidentate ligand is crucial for the high ortho-selectivity.Computational studies support outer-sphere X–H⋅⋅⋅O_(boryl) hydrogen bond interactions,which are strengthened by bidentate C^C ligand introduction.The method shows broad substrate scope and high functional group tolerance.展开更多
Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides ...Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.展开更多
The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure−property correlations at the nanoscale.H...The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure−property correlations at the nanoscale.However,a serious problem for metal nanocluster catalysts is that the ligands inhibit the catalytic activity through deactivating the surface of the nanoclusters.Here,we introduce a novel catalytic mode for metal nanoclusters,in which the nanoclusters initiate the catalysis via single electron transfer(SET)without destroying the integrity of nanoclusters,providing a solution for the contradiction between activity and stability of metal nanoclusters.We illustrated that the novel activation mode featured low catalyst loading(0.01 mol%),high TOF,mild reaction conditions,and easy recycling of catalyst in alkyne hydroborylation,which often suffered from poor selectivity,low functional group tolerance,etc.Furthermore,the catalyst[Au_(1)Cu_(14)(TBBT)_(12)(PPh_(3))_(6)]^(+)(TBBTH:p-tert-butylthiophenol)can be applied in highly efficient tandem processes such as hydroborylation−deuteration and hydroborylation−isomerization,demonstrating the utility of the introduced activation mode for metal nanoclusters.展开更多
Organoboron is well-developed and broadly utilized organometallic reagents in organic synthesis due to its extraordinary performances in transition-metal catalyzed C-C and C-X bonds construction. Catalytic C--H boryla...Organoboron is well-developed and broadly utilized organometallic reagents in organic synthesis due to its extraordinary performances in transition-metal catalyzed C-C and C-X bonds construction. Catalytic C--H borylation and further transformations catalyzed by transition metal catalysts in the absence of oxidants were well studied in decades. However, as known, transition metal catalyzed oxidative C-H borylations were not reviewed up to date. In this article the oxidative borylation of C(sp2)-H and C(sp3)-H bonds were summarized and their mechanisms were also accounted.展开更多
An efficient, transition-metal free, and practical approach to cis-bis(boryl)alkenes from various alkynes was disclosed in the presence of a catalytic amount of K_2CO_3 under mild conditions. Meanwhile, tetrasubstitut...An efficient, transition-metal free, and practical approach to cis-bis(boryl)alkenes from various alkynes was disclosed in the presence of a catalytic amount of K_2CO_3 under mild conditions. Meanwhile, tetrasubstituted alkenes and phenanthrene derivatives were readily constructed from the target diborylalkenes via Suzuki-Miyaura cross coupling.展开更多
Herein,we report the first electrochemical strategy for the borylation of aryl iodides via a radical pathway using current as a driving force.A mild reaction condition allows an assorted range of readily available ary...Herein,we report the first electrochemical strategy for the borylation of aryl iodides via a radical pathway using current as a driving force.A mild reaction condition allows an assorted range of readily available aryl iodides to be proficiently converted into synthetically valuable arylboronic esters under transition metal catalyst-free conditions.Moreover,this method also shows good functional group tolerance.Initial control mechanistic experiments reveal the formation of aryl radical as a key intermediate and the current plays an important role in the generation of radical intermediate.展开更多
Arene C(sp^(2))-H bond borylation offers direct and efficient access to aryl boronic esters.Using in situ catalyst activation and photoirradiation,the iron-catalysed C(sp^(2))-H borylation reaction of carboarenes,pyrr...Arene C(sp^(2))-H bond borylation offers direct and efficient access to aryl boronic esters.Using in situ catalyst activation and photoirradiation,the iron-catalysed C(sp^(2))-H borylation reaction of carboarenes,pyrroles,and indoles has been developed using only bench-stable pre-catalysts and reagents.Good functional group tolerance was observed including those not reported using previous methods(ArNH_(2),ArOH,ArSiR_(3),ArP(O)(O)_(2),ArC(O)NR_(2)).Mechanistic studies revealed iron-catalysed reductive deoxygenation,C—F protodefluorination,and a demethylation of aryl methyl ethers by C—O sigma bond hydroboration.展开更多
A radical-induced 1,2-α-boryl migration through radical polar crossover reactions has been described.In this work,in situ formed vinyldiboron“ate”complexes from alkenyl Grignard reagent and diborylalkanes react wit...A radical-induced 1,2-α-boryl migration through radical polar crossover reactions has been described.In this work,in situ formed vinyldiboron“ate”complexes from alkenyl Grignard reagent and diborylalkanes react with commercial radical precursors under light initiation.This three-component process enables diborylation of alkene.This protocol features high atom economy,a broad substrate scope as well as good functional group toleration with mild conditions.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
Main observation and conclusion Stereodefinedβ,γ-unsaturated carbony|compounds are important yet synthetically challenging units in natural products and drugs.Disclosed herein is a mild,rapid copper-catalyzed dibory...Main observation and conclusion Stereodefinedβ,γ-unsaturated carbony|compounds are important yet synthetically challenging units in natural products and drugs.Disclosed herein is a mild,rapid copper-catalyzed diborylation reaction of cross-conjugated enynones as a step-economic and modular approach to stereodefined multifunctionalizedβ,γ-unsaturated ketones by fine control of chemo-,regio-,Z/E and diastereoselectivity.The substrate scope was examined and a possible catalytic cycle was proposed to explain the multifaceted selectivity.展开更多
Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with all...Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.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supported by the Hong Kong Research Grants Council(27301720,17304021)National Natural Science Foundation of China(22122114,22122503,21790361).
文摘The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials.Facile,selective,and programmable routes to helicenes or heterohelicenes are highly desirable yet challenging for structure-chiroptical property relationship studies.Herein,we report the synthesis and characterization of NBN-doped helicenes with boron atoms in the inner rims,enabled by the highly regioselective one-pot borylation of rationally designed precursors with,namely,fold-in or pan-out manner.The incorporation of nonbonded boron and nitrogen atoms resulted in narrow-band emission and improved optical properties for the single-stranded carbon helix.In addition,numbers and arrangement modes of fused six-membered rings have distinct effects on configurational stability and chiroptical properties,revealing that BN-[6]H with strong circular dichroism is a promising candidate for chiral sensors.The combination of experimental and theoretical studies on these helical structures might provide insights into the design of helically chiral small-molecule-based sensors or emitters.
基金supported by the National Natural Science Foundation of China(21602096)。
文摘A simple electrochemically mediated method for the conversion of nitroarenes to aryl boronic esters is presented.Electrochemical borylation of a diverse range of nitroarenes,including the late-stage borylation of bioactive molecules,is furnished at room temperature under simple conditions,thereby demonstrating the broad utility and functional-group tolerance of this protocol.This transformation provides a convenient and practical access to aryl boronic esters from widely available nitroarenes,which would significantly streamline the synthetic process of diverse functionalized arenes.
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This work was supported by the National Natural Science Foundation of China(Nos.22171284 and 21602249)the Fundamental Research Funds for the Central Universities,the Research Funds of Renmin University of China(No.20XNLG20)the Public Computing Cloud Platform,Renmin University of China.
文摘We describe an iridium-catalyzed ortho-selective C–H borylation of unprotected anilines.The employing strongσ-donating cyclometalated mesoionic carbene as C^C bidentate ligand is crucial for the high ortho-selectivity.Computational studies support outer-sphere X–H⋅⋅⋅O_(boryl) hydrogen bond interactions,which are strengthened by bidentate C^C ligand introduction.The method shows broad substrate scope and high functional group tolerance.
文摘Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.
基金financially supported by the National Natural Science Foundation of China(Nos.92061110,21925303,21829501,21771186,21222301,21528303,and 21171170)the Anhui Provincial Natural Science Foundation(2108085Y05 and 2108085MB56)+1 种基金Collaborative Innovation Program of Hefei Science Center,CAS(Nos.2020HSCCIP005 and 2022HSC-CIP018)the Hefei National Laboratory for Physical Sciences at the Microscale(KF2020102).
文摘The emergence of metal nanoclusters with atomically precise compositions and structures provides an opportunity for in-depth investigation of catalysis mechanisms and structure−property correlations at the nanoscale.However,a serious problem for metal nanocluster catalysts is that the ligands inhibit the catalytic activity through deactivating the surface of the nanoclusters.Here,we introduce a novel catalytic mode for metal nanoclusters,in which the nanoclusters initiate the catalysis via single electron transfer(SET)without destroying the integrity of nanoclusters,providing a solution for the contradiction between activity and stability of metal nanoclusters.We illustrated that the novel activation mode featured low catalyst loading(0.01 mol%),high TOF,mild reaction conditions,and easy recycling of catalyst in alkyne hydroborylation,which often suffered from poor selectivity,low functional group tolerance,etc.Furthermore,the catalyst[Au_(1)Cu_(14)(TBBT)_(12)(PPh_(3))_(6)]^(+)(TBBTH:p-tert-butylthiophenol)can be applied in highly efficient tandem processes such as hydroborylation−deuteration and hydroborylation−isomerization,demonstrating the utility of the introduced activation mode for metal nanoclusters.
文摘Organoboron is well-developed and broadly utilized organometallic reagents in organic synthesis due to its extraordinary performances in transition-metal catalyzed C-C and C-X bonds construction. Catalytic C--H borylation and further transformations catalyzed by transition metal catalysts in the absence of oxidants were well studied in decades. However, as known, transition metal catalyzed oxidative C-H borylations were not reviewed up to date. In this article the oxidative borylation of C(sp2)-H and C(sp3)-H bonds were summarized and their mechanisms were also accounted.
基金supported by the National Natural Science Foundation(21772046)Program of Innovative Research Team of Huaqiao University(Z14X0047)+2 种基金the Recruitment Program of Global Experts(1000 Talents Plan)the Natural Science Foundation of Fujian Province(2016J01064)Postgraduates’ Innovative Fund in Scientific Research of Huaqiao University for K.Z
文摘An efficient, transition-metal free, and practical approach to cis-bis(boryl)alkenes from various alkynes was disclosed in the presence of a catalytic amount of K_2CO_3 under mild conditions. Meanwhile, tetrasubstituted alkenes and phenanthrene derivatives were readily constructed from the target diborylalkenes via Suzuki-Miyaura cross coupling.
基金the National Natural Science Foundation of China(Grant No.21772003).
文摘Herein,we report the first electrochemical strategy for the borylation of aryl iodides via a radical pathway using current as a driving force.A mild reaction condition allows an assorted range of readily available aryl iodides to be proficiently converted into synthetically valuable arylboronic esters under transition metal catalyst-free conditions.Moreover,this method also shows good functional group tolerance.Initial control mechanistic experiments reveal the formation of aryl radical as a key intermediate and the current plays an important role in the generation of radical intermediate.
基金S.P.T.thanks The Royal Society for a University Research Fel-lowship(RF191015)J.H.D.and S.P.T.acknowledge GSK and EPSRC(110002)The Royal Society(RF191015)for postdoctoral funding.L.B.acknowledges The Royal Society and The University of Edinburgh for a Ph.D.studentship(RF191015).
文摘Arene C(sp^(2))-H bond borylation offers direct and efficient access to aryl boronic esters.Using in situ catalyst activation and photoirradiation,the iron-catalysed C(sp^(2))-H borylation reaction of carboarenes,pyrroles,and indoles has been developed using only bench-stable pre-catalysts and reagents.Good functional group tolerance was observed including those not reported using previous methods(ArNH_(2),ArOH,ArSiR_(3),ArP(O)(O)_(2),ArC(O)NR_(2)).Mechanistic studies revealed iron-catalysed reductive deoxygenation,C—F protodefluorination,and a demethylation of aryl methyl ethers by C—O sigma bond hydroboration.
基金Financial supports from the National Natural Science Foundation of China(Nos.21772046,2193103,22001038)are gratefully acknowledged.
文摘A radical-induced 1,2-α-boryl migration through radical polar crossover reactions has been described.In this work,in situ formed vinyldiboron“ate”complexes from alkenyl Grignard reagent and diborylalkanes react with commercial radical precursors under light initiation.This three-component process enables diborylation of alkene.This protocol features high atom economy,a broad substrate scope as well as good functional group toleration with mild conditions.
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the National Natural Sci-ence Foundation of China(Nos.21672168,21971202)the Key Laboratory Construction Program of Xi'an Municipal Bureau of Science and Technology(No.201805056ZD7CG40)。
文摘Main observation and conclusion Stereodefinedβ,γ-unsaturated carbony|compounds are important yet synthetically challenging units in natural products and drugs.Disclosed herein is a mild,rapid copper-catalyzed diborylation reaction of cross-conjugated enynones as a step-economic and modular approach to stereodefined multifunctionalizedβ,γ-unsaturated ketones by fine control of chemo-,regio-,Z/E and diastereoselectivity.The substrate scope was examined and a possible catalytic cycle was proposed to explain the multifaceted selectivity.
基金supported by the National Natural Science Foundation of China (21831007)。
文摘Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.