Carbonyl compounds are abundant in nature and represent a substantial portion of biomass resources.Despite significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo...Carbonyl compounds are abundant in nature and represent a substantial portion of biomass resources.Despite significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate challenge.Herein,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single step.This method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material sciences.Mechanistic investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.展开更多
Palladium-catalyzed homo-coupling of arylboronic acids could proceed smoothly with a commercially available resin functionlised by phosphino or amino group as the ligand in supercritical carbon dioxide thereby offerin...Palladium-catalyzed homo-coupling of arylboronic acids could proceed smoothly with a commercially available resin functionlised by phosphino or amino group as the ligand in supercritical carbon dioxide thereby offering a simple and efficient protocol for the synthesis of symmetrical bi-aryl molecules and their higher homologues.展开更多
The efficient utilization of visible light catalysts for organic reactions necessitates not only the effective separation of photogenerated electrons and holes to participate in the reaction,but also their ability to ...The efficient utilization of visible light catalysts for organic reactions necessitates not only the effective separation of photogenerated electrons and holes to participate in the reaction,but also their ability to form key intermediates with reactant molecules.The present study successfully synthesized a crusiform-like mesoporous structure of nitrogen-doped carbon-coated Cu_(2)O/Cu(Cu_(2)O/Cu/N-C)with a Cu_(2)O/dual electron acceptor interface using etched HKUST-1 as the precursor.A series of theoretical and experimental studies have demonstrated that the Cu_(2)O/Cu/N-C interface in the photocatalytic homo-coupling of terminal alkynes not only effectively enhances the separation of photogenerated electron−hole pairs,but also facilitates the formation of the key intermediate[Cu_(2)O/Cu/N-C]-phenylacetylide and promotes the rearrangement of its internal charges.As a result,the homo-coupling reaction can be effectively facilitated.The primary reason for the functional role of Cu_(2)O/Cu/N-C interface lies in the downward bending of energy band from Cu_(2)O to N-doped C layers,induced by the different work functions of Cu_(2)O,Cu and N-doped C layers.Consequently,Cu_(2)O/Cu/N-C photocatalysts demonstrate exceptional photocatalytic activity in the homo-coupling reaction of terminal alkynes under blue-light irradiation and air atmosphere.The present study presents a novel research methodology for the development of highly efficient visible light catalysts to facilitate organic reactions in future applications.展开更多
A series of solvents were examined for the ligand free Pd（II）-catalyzed Suzuki reaction of 4-bromotoluene with phenylboronic acid. It was found that the PdCl2/i-PrOH system could efficiently inhibit the homo-couplin...A series of solvents were examined for the ligand free Pd（II）-catalyzed Suzuki reaction of 4-bromotoluene with phenylboronic acid. It was found that the PdCl2/i-PrOH system could efficiently inhibit the homo-coupling of phenylboronic acid and give a cross-coupling product in high yields. The substrates with a wide variety of functional groups were tolerated in the system. A possible mechanism for this system was proposed.展开更多
Owing to their inexpensive and environmentally friendly properties,iron-based catalysts have been actively investigated for new organic reactions.In this account,we summarized our recent results on iron-catalyzed cros...Owing to their inexpensive and environmentally friendly properties,iron-based catalysts have been actively investigated for new organic reactions.In this account,we summarized our recent results on iron-catalyzed cross-coupling reactions and homo-coupling reactions.With iron-based catalysts,we constructed diverse carbon-carbon bonds,i.e.,C(sp^2)-C(sp^3),C(sp^3)-C(sp^3),C(sp^3)-C(sp^2)and C(sp^2)-C(sp^2)bonds.In order to demonstrate the usefulness of our iron protocol,we also carried out these reactions on gram-scale reactions,leading to good yields.展开更多
O_(x)idative couplings of aliphatic alkynes are crucial for the production of naturally occurring 1,3-diynes.Herein we report the novel approach for effective synthesis of unsaturated coordinated N doped copper oxides...O_(x)idative couplings of aliphatic alkynes are crucial for the production of naturally occurring 1,3-diynes.Herein we report the novel approach for effective synthesis of unsaturated coordinated N doped copper oxides(N-CuO_(x))catalyst,and uncover that N-CuO_(x) catalyst as an additive-free and cost-effective heterogeneous catalyst has highly catalytic performance for directly oxidative coupling of aliphatic alkynes.The key to achieve efficient oxidative coupling of aliphatic alkynes is the synergistic effect of N species and uncoordinated O/Cu species caused by N dopants,which undergoes the Langmuir–Hinshelwood reaction mechanism.The N-CuO_(x) catalyst displays~89.1%yield for hexadeca-7,9-diyne under mild conditions and stable reusability(5 cycles),showing significant advances compared with the traditionally copper oxides.These findings highlight the heteroatom dopants that provide a new methodology for designing efficient copper catalysts in synthesis of naturally occurring 1,3-diynes.展开更多
基金National Natural Science Foundation of China(NSFC,No.21971093)the Fundamental Research Funds for the Central Universities(No.lzujbky-2021-sp53)+2 种基金the International Joint Research centre for Green Catalysis and Synthesis(No.2016B01017)The Science and Technology Major Program of Gansu Province of China(No.22ZD6FA006)the 111 project for support of our research.We also thank the Canada Research Chair(Tier I)foundation,the E.B。
文摘Carbonyl compounds are abundant in nature and represent a substantial portion of biomass resources.Despite significant recent progress in homo-coupling of carbonyl compounds,achieving their deoxyfunctionalization homo-coupling remains a highly intricate challenge.Herein,we report an entirely novel reaction paradigm:the trifluoromethylative homo-coupling of carbonyl compounds via hydrazones,which enables the formation of three C(sp^(3))-C(sp^(3))bonds in a single step.This method provides a new pathway for synthesizing trifluoromethylative coupling product which has unique applications in both fields of medical and material sciences.Mechanistic investigations have unveiled that the formation of a trifluoromethyl-substituted benzyl radical plays a pivotal role as a key intermediate in this reaction.
文摘Palladium-catalyzed homo-coupling of arylboronic acids could proceed smoothly with a commercially available resin functionlised by phosphino or amino group as the ligand in supercritical carbon dioxide thereby offering a simple and efficient protocol for the synthesis of symmetrical bi-aryl molecules and their higher homologues.
基金supported by the Xuzhou Key Research and Development Program(Social Development)(No.KC23298)the National Natural Science Foundation of China(No.22271122)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20211549)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX23_2903).
文摘The efficient utilization of visible light catalysts for organic reactions necessitates not only the effective separation of photogenerated electrons and holes to participate in the reaction,but also their ability to form key intermediates with reactant molecules.The present study successfully synthesized a crusiform-like mesoporous structure of nitrogen-doped carbon-coated Cu_(2)O/Cu(Cu_(2)O/Cu/N-C)with a Cu_(2)O/dual electron acceptor interface using etched HKUST-1 as the precursor.A series of theoretical and experimental studies have demonstrated that the Cu_(2)O/Cu/N-C interface in the photocatalytic homo-coupling of terminal alkynes not only effectively enhances the separation of photogenerated electron−hole pairs,but also facilitates the formation of the key intermediate[Cu_(2)O/Cu/N-C]-phenylacetylide and promotes the rearrangement of its internal charges.As a result,the homo-coupling reaction can be effectively facilitated.The primary reason for the functional role of Cu_(2)O/Cu/N-C interface lies in the downward bending of energy band from Cu_(2)O to N-doped C layers,induced by the different work functions of Cu_(2)O,Cu and N-doped C layers.Consequently,Cu_(2)O/Cu/N-C photocatalysts demonstrate exceptional photocatalytic activity in the homo-coupling reaction of terminal alkynes under blue-light irradiation and air atmosphere.The present study presents a novel research methodology for the development of highly efficient visible light catalysts to facilitate organic reactions in future applications.
文摘A series of solvents were examined for the ligand free Pd（II）-catalyzed Suzuki reaction of 4-bromotoluene with phenylboronic acid. It was found that the PdCl2/i-PrOH system could efficiently inhibit the homo-coupling of phenylboronic acid and give a cross-coupling product in high yields. The substrates with a wide variety of functional groups were tolerated in the system. A possible mechanism for this system was proposed.
基金financed by National Natural Science Foundation of China (Nos. 21672181, 21272199)GRF/RGC (Nos. 403012, CUHK14309216, CUHK14303815)+1 种基金grant to the State Key Laboratory of Synthetic Chemistry from the Innovation and Technology Commission, The Chinese Academy of Sciences-Croucher Foundation Funding Scheme for Joint LaboratoriesDirect Grant (No. 4053325) from The Chinese University of Hong Kong
文摘Owing to their inexpensive and environmentally friendly properties,iron-based catalysts have been actively investigated for new organic reactions.In this account,we summarized our recent results on iron-catalyzed cross-coupling reactions and homo-coupling reactions.With iron-based catalysts,we constructed diverse carbon-carbon bonds,i.e.,C(sp^2)-C(sp^3),C(sp^3)-C(sp^3),C(sp^3)-C(sp^2)and C(sp^2)-C(sp^2)bonds.In order to demonstrate the usefulness of our iron protocol,we also carried out these reactions on gram-scale reactions,leading to good yields.
基金Supported by NSFC (20172063) The Major State Basic Research Development Program (GrantNo. G2000077506-A) and The project of Chinese Academy of Sciences.
基金supported by the“Key Program for International S&T Cooperation Projects of China”(No.2017YFE0124300)Anhui Provincial Natural Science Foundation of China(No.2008085M47)+1 种基金Key Projects of the Department of Education of Anhui Province of China(No.RZ2000003450)The authors thank the beamline BL14W1 at Shanghai Synchrotron Radiation Facility(SSRF).
文摘O_(x)idative couplings of aliphatic alkynes are crucial for the production of naturally occurring 1,3-diynes.Herein we report the novel approach for effective synthesis of unsaturated coordinated N doped copper oxides(N-CuO_(x))catalyst,and uncover that N-CuO_(x) catalyst as an additive-free and cost-effective heterogeneous catalyst has highly catalytic performance for directly oxidative coupling of aliphatic alkynes.The key to achieve efficient oxidative coupling of aliphatic alkynes is the synergistic effect of N species and uncoordinated O/Cu species caused by N dopants,which undergoes the Langmuir–Hinshelwood reaction mechanism.The N-CuO_(x) catalyst displays~89.1%yield for hexadeca-7,9-diyne under mild conditions and stable reusability(5 cycles),showing significant advances compared with the traditionally copper oxides.These findings highlight the heteroatom dopants that provide a new methodology for designing efficient copper catalysts in synthesis of naturally occurring 1,3-diynes.
