Herein,we report the migratory hydroarylation of unactivated alkenes with aryl iodides using native and weakly coordinating amide directors under mild conditions.Synergistic coordination of the monodentate directing g...Herein,we report the migratory hydroarylation of unactivated alkenes with aryl iodides using native and weakly coordinating amide directors under mild conditions.Synergistic coordination of the monodentate directing group and the ligand enable the highly regioselective migratory hydroarylation via a chain walking process to form the thermodynamically stable five-membered nickelacyle intermediate.The protocol provides a variety of valuableα-aryl-substituted alkylamine products,and exhibited good functional group tolerance.The modification of bioactive compounds such as fenofibrate and indomethacin further highlights the synthetic value of this protocol.展开更多
Aliphatic C(sp^(3))-H moieties are ubiquitous in numerous organic compounds.Direct functionalization of inert C(sp^(3))-H bonds is a powerful and straightforward approach for the efficient construction of diverse carb...Aliphatic C(sp^(3))-H moieties are ubiquitous in numerous organic compounds.Direct functionalization of inert C(sp^(3))-H bonds is a powerful and straightforward approach for the efficient construction of diverse carbon-carbon or carbon-heteroatom bonds.Chelating group directed metal-catalyzed remote functionalization of readily available alkenes has emerged as an appealing strategy for rapidly accessing various value-added aliphatic molecules.With the aid of directing groups,variousα-,β-andγ-functionalized alkanes could be synthesized smoothly with excellent regioselectivity.The preferred formation of a stable five-or six-membered metallacycle intermediate terminates the chain-walking at a specific methylene site,which serves as the driving force for excellent site-selective migratory functionalization.This review herein is aimed at summarizing the recent progress on the metal-catalyzed regiodivergent functionalization of unactivated alkenes by merging alkene isomerization and cross-coupling with the assistance of directing auxiliary.Last but not least,the current situations and future directions in this field are highlighted and discussed.展开更多
The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, ...The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.展开更多
"Chain-walking"reactions could realize to modify a molecule at the position far awayfrom the active site.It has been a hot topic in the research field of organic synthesis.As a number of achievements have be..."Chain-walking"reactions could realize to modify a molecule at the position far awayfrom the active site.It has been a hot topic in the research field of organic synthesis.As a number of achievements have been made by researchers,the products of transition metal-catalyzed chain-walking reactions couldbe obtained with good enantioselectivity.This review summarized the researches on the asymmetric chain-walking reactions catalyzed by transition metal in the past decade.These works are classified according to the species of metal catalysts.展开更多
Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane(MMAO), were tested in the polymerization of higher α-olefin(1-hexene, 1-decene and 1-hexadec...Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane(MMAO), were tested in the polymerization of higher α-olefin(1-hexene, 1-decene and 1-hexadecene) under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers(42-88/1000 C) with high molecular weights(Mn:(4.3-15.2) × 10^4 g·mol^-1) and narrow molecular weight distribution(Mw/Mn = 1.13-1.29, RT), which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction.展开更多
Despite the 1,2-difunctionalization reactions of styrenes have been well developed, the 1,1-regioselective addition reaction remains challenging. We disclose herein a palladium-catalyzed, highly 1,1-regioselective alk...Despite the 1,2-difunctionalization reactions of styrenes have been well developed, the 1,1-regioselective addition reaction remains challenging. We disclose herein a palladium-catalyzed, highly 1,1-regioselective alkenylboration of styrenes by using alkenyl triflates and a diboron reagent as the coupling partners. A wide scope of styrenes derivatives and alkenyl triflates participate this reaction to provide the corresponding allyl boronates with high regioisomeric ratios. The success of this reaction is ascribed to the application of 1,10-phenanthroline-derivated ligand and the addition of ammonium chloride salt. Moreover, acrylate esters can also selectively afford the 1,1-alkenylboration products under the same reaction conditions.展开更多
Chiral 1,3-substituted fragments are ubiquitous in pharmaceutical molecules and natural products,prompting the development of numerous methods to access these structures.Nonetheless,devising synthetic routes for compl...Chiral 1,3-substituted fragments are ubiquitous in pharmaceutical molecules and natural products,prompting the development of numerous methods to access these structures.Nonetheless,devising synthetic routes for complex chiral architectures in practical applications typically demands years of expertise.Herein,we developed a nickel-catalyzed enantioselective migratory arylboration reaction of allylboronic esters using a chiral 1,2-diamine ligand,yielding a range of chiral 1,3-bis(boronates)with high enantioselectivity.The protocol is characterized by its use of commercially available substrates,mild reaction conditions,user-friendly procedures,and a broad substrate compatibility.Moreover,we demonstrate the practicality and application potential of this reaction by synthesizing several key drug intermediates.展开更多
A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor ligands.This method enab...A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor ligands.This method enables the synthesis of diverseβ-orγ-branched aromatic N-heterocycles.The mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable regioselectivity.Importantly,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.展开更多
Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive compounds.While significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-...Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive compounds.While significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain scarce.This study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,4-cyclohexadiene.This innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis configuration.The resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.展开更多
The transition-metal-catalyzed migratory functionalization has emerged as a robust protocol for the building of C–C bonds remote from the“initiation”position.However,a similar strategy for the construction of quate...The transition-metal-catalyzed migratory functionalization has emerged as a robust protocol for the building of C–C bonds remote from the“initiation”position.However,a similar strategy for the construction of quaternary carbon centers is still underdeveloped and only a limited number of reports exist.Herein,we report a nickel-catalyzed migratory hydrocyanation of unconjugated dienes to construct remote cyano-substituted quaternary carbon centers.This transformation features exceptional regioselectivity,mild reaction conditions,broad substrate scope and high yields.The synthetic utility of this method has been highlighted by a series of product derivatizations,and the potential of this transformation has been extended to synthesize TRPV1 antagonist and the key intermediate in the total synthesis of quebrachamine.Density functional theory(DFT)studies unveiled that the specific catalytic pocket assumed a significant role in the selective formation of cyano-substituted quaternary carbon centers.展开更多
Herein,we disclose a ligand-controlled,directing group-assisted strategy to facilitate NiH-catalyzed hydroalkynylation of allyl amides at remoteα-position adjacent to nitrogen and initial olefinic site in a predictab...Herein,we disclose a ligand-controlled,directing group-assisted strategy to facilitate NiH-catalyzed hydroalkynylation of allyl amides at remoteα-position adjacent to nitrogen and initial olefinic site in a predictable and switchable manner.Bromoalkynedependent regiodivergent hydroalkynylation and asymmetric hydroalkynylation with a wide alkyne scope were achieved,producingα-and(enantioenriched)β-branched alkynyl-functionalized amine derivatives from the same raw materials.The formation of a carbonyl-ligated 5-or 6-membered nickelacycle intermediate via Ni migration or nonmigration was believed to be the key step in controlling the regioselectivity.This asymmetric protocol could be applied to synthesizing other value-added chiral aliphatic amines.展开更多
Recently,the chain-walking ethylene polymerization strategy has garnered widespread attention as an efficient and straightforward method for preparing polyolefin elastomers.In this study,a series of 2,4,8-triarylnapht...Recently,the chain-walking ethylene polymerization strategy has garnered widespread attention as an efficient and straightforward method for preparing polyolefin elastomers.In this study,a series of 2,4,8-triarylnaphthyl iminopyridyl nickel catalysts were synthesized and used in ethylene polymerization.These catalysts demonstrated moderate catalytic activity(105 g mol^(−1) h^(−1)),producing high-molecular-weight(up to 145.5 kg/mol)polyethylene materials with high branching degrees(75−95/1000C)and correspondingly low melting points.Detailed analysis using 13C NMR spectroscopy revealed that the polyethylenes primarily featured methyl and long-chain branches.Mechanical testing of the polyethylene samples obtained from catalysts Ni1−Ni3 exhibited moderate stress at break(4.64−6.97 MPa)coupled with a very high strain at break(1650−3752%),indicating their very good ductility.Furthermore,these polyethylenes showcased great elastic recovery abilities,with strain recovery values ranging from 72%to 85%.In contrast,the polyethylene produced by Ni4 displayed notably inferior tensile strength(0.16 MPa)and tensile recovery(43%).To the best of our knowledge,this study represents the inaugural utilization of a nickel iminopyridyl catalyst in the preparation of a polyethylene thermoplastic elastomer.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21901185 and 22301216)funds provided by Tianjin Normal University。
文摘Herein,we report the migratory hydroarylation of unactivated alkenes with aryl iodides using native and weakly coordinating amide directors under mild conditions.Synergistic coordination of the monodentate directing group and the ligand enable the highly regioselective migratory hydroarylation via a chain walking process to form the thermodynamically stable five-membered nickelacyle intermediate.The protocol provides a variety of valuableα-aryl-substituted alkylamine products,and exhibited good functional group tolerance.The modification of bioactive compounds such as fenofibrate and indomethacin further highlights the synthetic value of this protocol.
基金the National Natural Science Foundation of China(No.22001116)the Basic and Applied Basic Research Foundation of Guangdong Province(No.2020A1515110816)funds provided by Changzhou University(No.ZMF23020217)。
文摘Aliphatic C(sp^(3))-H moieties are ubiquitous in numerous organic compounds.Direct functionalization of inert C(sp^(3))-H bonds is a powerful and straightforward approach for the efficient construction of diverse carbon-carbon or carbon-heteroatom bonds.Chelating group directed metal-catalyzed remote functionalization of readily available alkenes has emerged as an appealing strategy for rapidly accessing various value-added aliphatic molecules.With the aid of directing groups,variousα-,β-andγ-functionalized alkanes could be synthesized smoothly with excellent regioselectivity.The preferred formation of a stable five-or six-membered metallacycle intermediate terminates the chain-walking at a specific methylene site,which serves as the driving force for excellent site-selective migratory functionalization.This review herein is aimed at summarizing the recent progress on the metal-catalyzed regiodivergent functionalization of unactivated alkenes by merging alkene isomerization and cross-coupling with the assistance of directing auxiliary.Last but not least,the current situations and future directions in this field are highlighted and discussed.
文摘The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature.
基金Financial support was provided by the National Natural Science Foundation of China(No.21801181).
文摘"Chain-walking"reactions could realize to modify a molecule at the position far awayfrom the active site.It has been a hot topic in the research field of organic synthesis.As a number of achievements have been made by researchers,the products of transition metal-catalyzed chain-walking reactions couldbe obtained with good enantioselectivity.This review summarized the researches on the asymmetric chain-walking reactions catalyzed by transition metal in the past decade.These works are classified according to the species of metal catalysts.
基金financially supported by the Fundamental Research Funds for the Central Universities (WK2060200025)Advanced Catalysis and Green Manufacturing Collaborative Innovation Center (ACGM2016-06-01)Yixing Taodu Ying Cai Program
文摘Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane(MMAO), were tested in the polymerization of higher α-olefin(1-hexene, 1-decene and 1-hexadecene) under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers(42-88/1000 C) with high molecular weights(Mn:(4.3-15.2) × 10^4 g·mol^-1) and narrow molecular weight distribution(Mw/Mn = 1.13-1.29, RT), which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction.
基金This work was supported by grants from the National Natural Science Foundation of China(No.22122107)the Fundamental Research Funds for Central Universities(No.2042021kf0190).
文摘Despite the 1,2-difunctionalization reactions of styrenes have been well developed, the 1,1-regioselective addition reaction remains challenging. We disclose herein a palladium-catalyzed, highly 1,1-regioselective alkenylboration of styrenes by using alkenyl triflates and a diboron reagent as the coupling partners. A wide scope of styrenes derivatives and alkenyl triflates participate this reaction to provide the corresponding allyl boronates with high regioisomeric ratios. The success of this reaction is ascribed to the application of 1,10-phenanthroline-derivated ligand and the addition of ammonium chloride salt. Moreover, acrylate esters can also selectively afford the 1,1-alkenylboration products under the same reaction conditions.
基金supported by Guangdong Basic and Applied Basic Research Foundation(2024A1515011689).
文摘Chiral 1,3-substituted fragments are ubiquitous in pharmaceutical molecules and natural products,prompting the development of numerous methods to access these structures.Nonetheless,devising synthetic routes for complex chiral architectures in practical applications typically demands years of expertise.Herein,we developed a nickel-catalyzed enantioselective migratory arylboration reaction of allylboronic esters using a chiral 1,2-diamine ligand,yielding a range of chiral 1,3-bis(boronates)with high enantioselectivity.The protocol is characterized by its use of commercially available substrates,mild reaction conditions,user-friendly procedures,and a broad substrate compatibility.Moreover,we demonstrate the practicality and application potential of this reaction by synthesizing several key drug intermediates.
基金supported by the Dalian Institute of Chemical Physics,the Chinese Academy of Sciencesthe National Natural Science Foundation of China(21472186,21272231)。
文摘A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor ligands.This method enables the synthesis of diverseβ-orγ-branched aromatic N-heterocycles.The mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable regioselectivity.Importantly,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.
基金supported by the National Natural Science Foundation of China(22122107).
文摘Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive compounds.While significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain scarce.This study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,4-cyclohexadiene.This innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis configuration.The resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.
基金the National Natural Science Foundation of China(22278265,U22B20137 and 22203069)the Zhejiang Provincial Natural Science Foundation of China(LR24B020002)+1 种基金the start-up funding from Hangzhou Normal University(4095C50222204165 and 4095C50223204074)the Interdisciplinary Research Project of Hangzhou Normal University(2024JCXK04)for financial support of this research。
文摘The transition-metal-catalyzed migratory functionalization has emerged as a robust protocol for the building of C–C bonds remote from the“initiation”position.However,a similar strategy for the construction of quaternary carbon centers is still underdeveloped and only a limited number of reports exist.Herein,we report a nickel-catalyzed migratory hydrocyanation of unconjugated dienes to construct remote cyano-substituted quaternary carbon centers.This transformation features exceptional regioselectivity,mild reaction conditions,broad substrate scope and high yields.The synthetic utility of this method has been highlighted by a series of product derivatizations,and the potential of this transformation has been extended to synthesize TRPV1 antagonist and the key intermediate in the total synthesis of quebrachamine.Density functional theory(DFT)studies unveiled that the specific catalytic pocket assumed a significant role in the selective formation of cyano-substituted quaternary carbon centers.
基金supported by the National Natural Science Foundation of China(grant no.21901185)funds provided by Tianjin Normal University,China.
文摘Herein,we disclose a ligand-controlled,directing group-assisted strategy to facilitate NiH-catalyzed hydroalkynylation of allyl amides at remoteα-position adjacent to nitrogen and initial olefinic site in a predictable and switchable manner.Bromoalkynedependent regiodivergent hydroalkynylation and asymmetric hydroalkynylation with a wide alkyne scope were achieved,producingα-and(enantioenriched)β-branched alkynyl-functionalized amine derivatives from the same raw materials.The formation of a carbonyl-ligated 5-or 6-membered nickelacycle intermediate via Ni migration or nonmigration was believed to be the key step in controlling the regioselectivity.This asymmetric protocol could be applied to synthesizing other value-added chiral aliphatic amines.
基金supported by Natural Science Foundation of Anhui Province(2108085Y06).
文摘Recently,the chain-walking ethylene polymerization strategy has garnered widespread attention as an efficient and straightforward method for preparing polyolefin elastomers.In this study,a series of 2,4,8-triarylnaphthyl iminopyridyl nickel catalysts were synthesized and used in ethylene polymerization.These catalysts demonstrated moderate catalytic activity(105 g mol^(−1) h^(−1)),producing high-molecular-weight(up to 145.5 kg/mol)polyethylene materials with high branching degrees(75−95/1000C)and correspondingly low melting points.Detailed analysis using 13C NMR spectroscopy revealed that the polyethylenes primarily featured methyl and long-chain branches.Mechanical testing of the polyethylene samples obtained from catalysts Ni1−Ni3 exhibited moderate stress at break(4.64−6.97 MPa)coupled with a very high strain at break(1650−3752%),indicating their very good ductility.Furthermore,these polyethylenes showcased great elastic recovery abilities,with strain recovery values ranging from 72%to 85%.In contrast,the polyethylene produced by Ni4 displayed notably inferior tensile strength(0.16 MPa)and tensile recovery(43%).To the best of our knowledge,this study represents the inaugural utilization of a nickel iminopyridyl catalyst in the preparation of a polyethylene thermoplastic elastomer.