The asymmetric conjugate additions of aryl Grignard reagents to trisubstituted enones by chiral P,N ligand L6 with low catalyst loading(0.25–1.0 mol%)are disclosed.Chiral 2-ester chromanone and its analogs bearing a ...The asymmetric conjugate additions of aryl Grignard reagents to trisubstituted enones by chiral P,N ligand L6 with low catalyst loading(0.25–1.0 mol%)are disclosed.Chiral 2-ester chromanone and its analogs bearing a quaternary stereogenic centers at C2 position were produced in high to excellent yields,enantioselectivities and high turnover number.The notable features of this reaction include its broad substrate scope,complete 1,4-addition regioselectivities,applicability to both batch and flow for large scale synthesis.This report develops an efficient strategy to apply aryl Grignard reagents in asymmetric 1,4-conjugation reactions and provides a direct method to incorporate quaternary chiral centers toward the synthesis of biologically relevant chromanone derivatives.展开更多
We describe a convenient method for the synthesis of 1,2-disubstituted acetylenes via a cross-coupling reaction of （bromoethynyl）benzene with Grignard reagents. The reaction of （bromoethynyl）benzene （1 mmol） wit...We describe a convenient method for the synthesis of 1,2-disubstituted acetylenes via a cross-coupling reaction of （bromoethynyl）benzene with Grignard reagents. The reaction of （bromoethynyl）benzene （1 mmol） with Grignard reagent （1.3 mmol） mediated by NiCl2 （4 mol%） and （p-CH3Ph）3P （8 mol%） in THF could produce 1,2-disubstituted acetylenes in good yields at room temperature.展开更多
1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of pr...1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of preparing fused heterocyclic compounds was offered by 1,3-dipolar cycloaddition reaction of silyl nitronates to 1.展开更多
Polymeric Grignard Reagent (PGR) based on the chloromethylated poly(ST-co-DVB) resinhas been prepared by means of anthracene-magnesium complex in THF (Anth-Mg-THF), andpolymer matrix with long polymethylene spacer was...Polymeric Grignard Reagent (PGR) based on the chloromethylated poly(ST-co-DVB) resinhas been prepared by means of anthracene-magnesium complex in THF (Anth-Mg-THF), andpolymer matrix with long polymethylene spacer was synthesized via the coupling reaction betweenPGR and α, ω-dibromoalkanes. Based on the studies of factors affecting the coupling, such ascatalyst,reaction time,the length of spacer etc.,this paper offers the optimal reaction conditionsand three typical experiment procedures. The mechanism for the formation and coupling reactionof PGR are also discussed.展开更多
l-α-biaomo-2,3,4,6-tetra-O-acetyl-D-giucopyranose reacts with Grignard eagents prepared frorn the acnvated magnesium under very mild condition to ellord C- glucosides in a very high yield compared with Grignard Reage...l-α-biaomo-2,3,4,6-tetra-O-acetyl-D-giucopyranose reacts with Grignard eagents prepared frorn the acnvated magnesium under very mild condition to ellord C- glucosides in a very high yield compared with Grignard Reagent prepared from usual method.β-anomer predominates in the reaction, mixture The configuration of anomers was assigned by 13C NMR spectra.展开更多
The present paper narrates the addition of 5-trimethylsilylcyclohex-3-enone to Grig-nard reagent to give 1-substituted 5-trimethylsilylcyclohex-3-enol in a good yield. The stereochemistry of the addition reaction and ...The present paper narrates the addition of 5-trimethylsilylcyclohex-3-enone to Grig-nard reagent to give 1-substituted 5-trimethylsilylcyclohex-3-enol in a good yield. The stereochemistry of the addition reaction and their products are discussed.展开更多
Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(...Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(PPh3)4 to afford (Z)-1,2-disubstituted vinylselenides 3, which were cross-coupled with Grignard reagents in the presence of (PPh3)2NiCl2 to give trisubstituted alkenes 4 stereoselectively in good yields.展开更多
Polymer-supported selenovinyl bromide, easily prepared from polymer-supported selenenyl bromide with acetylene, reacts with different Grignard reagents using a step-by-step strategy to obtain （E）-1, 2-disubstituted ...Polymer-supported selenovinyl bromide, easily prepared from polymer-supported selenenyl bromide with acetylene, reacts with different Grignard reagents using a step-by-step strategy to obtain （E）-1, 2-disubstituted ethenes in good yields.展开更多
The precise synthesis of polymer with narrow molecular weight distribution(?)and well-defined architectures is very essential to exploring the functions and properties of polymer materials.Here,a universal polymerizat...The precise synthesis of polymer with narrow molecular weight distribution(?)and well-defined architectures is very essential to exploring the functions and properties of polymer materials.Here,a universal polymerization method capable of low?and reactive hydrogen compatibility is reported by introducing super-Grignard reagents(R_(2)Mg?Li Cl)into polymer chemistry.Under mild conditions,various monomers,including nonpolar polystyrene and 4-methoxystyrene that cannot be initiated by Grignard reagents,and polar methacrylate,are successfully polymerized with full monomer conversion and low?.This approach is amenable to wide varieties of initiators,polymerization temperature,and feed ratio,which makes it attractive for applications in polymer synthesis.By adding methanol and water during the polymerization process,the reactive hydrogen compatibility of this method is confirmed,which makes this method avoid the rigorous restriction on polymerization conditions of anionic polymerization.Moreover,chain extension polymerization and block copolymerization are achieved and demonstrate the livingness of chain propagation,enabling the facile synthesis of well-defined macromolecular architectures.This work therefore expands the methodology libraries of living polymerization,which may cause inspirations to polymer science.展开更多
The reaction of 2-substituted imidazolinium salt with bis-Grignard reagents is reported and a new method for the synthesis of symmetric diketones from carboxylic acids and bis-Grignard reagents is provided.
Cyclododecanedione and 1, 8-cyclotetradecanedione were prepared from bis-Grig- nard reagent and dinitriles. This is a convenient synthetic method for large-ring cycloalkanediones.
Arylamines constitute a fundamental class of organic compounds critical to pharmaceuticals,dyes,and advanced materials.The direct synthesis of arylamines from nitro compounds demonstrates significant advantages in ste...Arylamines constitute a fundamental class of organic compounds critical to pharmaceuticals,dyes,and advanced materials.The direct synthesis of arylamines from nitro compounds demonstrates significant advantages in step economy,cost efficiency,and functional group compatibility.However,conventional methodologies frequently necessitate transition metal catalysts or excessive reducing agents,limiting their practical applicability.Herein,we introduce a highly efficient photochemical protocol for the synthesis of arylamines from readily accessible nitro compounds and Grignard reagents under purple light(390—395 nm)irradiation,eliminating the requirement for transition metal catalysts or external reducing agents.This protocol exhibits exceptional tolerance to sterically hindered substrates and sensitive functional groups.Preliminary mechanistic investigations suggest the involvement of nitrosoarenes and diarylamine nitrogen radicals as key intermediates in the reaction pathway.展开更多
Indoles are essential heterocycles in natural products,biological chemistry,and medicinal chemistry.Efficient approaches to their synthesis,therefore,remain in demand.Herein is reported a novel and scalable method to ...Indoles are essential heterocycles in natural products,biological chemistry,and medicinal chemistry.Efficient approaches to their synthesis,therefore,remain in demand.Herein is reported a novel and scalable method to produce a wide variety of indoles by combining Grignard reagents and 2-fluorobenzyl cyanides(59 examples,45%-95%yields).The Grignard reagent adds to the nitrile to give a metalated imine that undergoes S_(N)Ar with unactivated C-F bonds.This strategy installs the R group of RMgX at the indole 2-position,and it is noteworthy that a diverse array of Grignard reagents(aryl,alkyl,vinyl,and cyclopropyl)provide the desired heterocyclic products.The resulting N-magnesiated indole can be in situ functionalized at the 3-position with alkyl halides or functionalized on the nitrogen with silyl chlorides.This method enables the synthesis of indoles with functional groups at each position of the indole backbone(C4-C7),providing handles for further functionalization.展开更多
The structure of osthole has been modified to improve its larvicidal activity against mosquitoes. A new efficient synthesis of osthole derivatives with Grignard reagents has been developed, which employs CuI and LiCI ...The structure of osthole has been modified to improve its larvicidal activity against mosquitoes. A new efficient synthesis of osthole derivatives with Grignard reagents has been developed, which employs CuI and LiCI as pro- moters and covers a broad range of substrates to afford the corresponding products in mild to good yields （up to 83%）. Bio-activity evaluation showed that several products exhibited better activities than osthole.展开更多
Diethyl (1-cyanoethyl) phosphorate 1 was reacted with n-butyl-lithium in tetrahydrofuran (THF) at - 78 °C and the resulting carbanion 2 reacted with perfluoroalkanoic add anhydride to afford perfluoroacylated pho...Diethyl (1-cyanoethyl) phosphorate 1 was reacted with n-butyl-lithium in tetrahydrofuran (THF) at - 78 °C and the resulting carbanion 2 reacted with perfluoroalkanoic add anhydride to afford perfluoroacylated phosphorate 3. Without isolation 3 was attacked by Grignard reagents giving perfluoroalkylated α, β-unsaturated nitriles in 46%-88% yields with high Z-stereoselectivity (Z: E = 89–62:11–38).展开更多
1,3-Bis(2,6-diisopropylphenyl)imidazolium chloride, [DIPrim]Cl, was used to produce a novel iron(III)-containing imidazolium salt [DIPrim][FeCl 4 ], which included a N,N-diarylimidazolium cation (R = 2,6-diisopropylph...1,3-Bis(2,6-diisopropylphenyl)imidazolium chloride, [DIPrim]Cl, was used to produce a novel iron(III)-containing imidazolium salt [DIPrim][FeCl 4 ], which included a N,N-diarylimidazolium cation (R = 2,6-diisopropylphenyl), [DIPrim] + , and tetrachloroferrate(III) anion, [FeCl 4 ]. This compound was an effective and easy-to-use catalyst for the cross-coupling of aryl Grignard reagents with primary and secondary alkyl halides bearing -hydrogens. After simply decanting the cross-coupling product in the ether layer, [DIPrim][FeCl 4 ] could be reused in at least four successive runs without significant loss of catalytic activity.展开更多
A new synthetic method of ketones from substituted benzimidazolium salts and Grignard reagents is reported. The influences of the various Grignard reagents on the yield of ketones and the mechanism are discussed.
A series of iron(III)-containing imidazolium salts of the general formula [DRim][FeX 4 ] (R=2,6-diisopropylphenyl, IPr, X=Cl, 1; R=IPr, X=Br, 2; R=tertbutyl, t Bu, X=Cl, 3; R=isopropyl, i Pr, X=Cl, 4; R=benzyl, Bn, X=...A series of iron(III)-containing imidazolium salts of the general formula [DRim][FeX 4 ] (R=2,6-diisopropylphenyl, IPr, X=Cl, 1; R=IPr, X=Br, 2; R=tertbutyl, t Bu, X=Cl, 3; R=isopropyl, i Pr, X=Cl, 4; R=benzyl, Bn, X=Cl, 5; R=Bn, X=Br, 6) have been prepared in high yields via reactions of anhydrous ferric halides with equivalent of the corresponding N,N-dihydro- carby-limidazolium halides, where 2-6 are novel ones. All of the complexes were characterized by elemental analysis, Raman spectroscopy, electrospray ionization mass spectroscopy, and X-ray crystallography for 1 and 2. All of them were non-hygroscopic and air-stable, with four of them existing as solids (1-4) and two as liquids (5 and 6) at room temperature. A preliminary catalytic study on the coupling of 4-tolylmagnesium bromide with cyclohexyl bromide revealed that 1 and 3 possessed the highest activity. In comparison, 2, 4 and 5 exhibited moderate activity and the least active complex was 6.展开更多
A facile and efficient method for the formylation of Grignard reagent was reported, and a new approach for the preparation of aldehydes from Grignard reagent and benzimidazolium salts was provided.
基金the financial support from the Sichuan Science and Technology Program(No.2022NSFSC0619)。
文摘The asymmetric conjugate additions of aryl Grignard reagents to trisubstituted enones by chiral P,N ligand L6 with low catalyst loading(0.25–1.0 mol%)are disclosed.Chiral 2-ester chromanone and its analogs bearing a quaternary stereogenic centers at C2 position were produced in high to excellent yields,enantioselectivities and high turnover number.The notable features of this reaction include its broad substrate scope,complete 1,4-addition regioselectivities,applicability to both batch and flow for large scale synthesis.This report develops an efficient strategy to apply aryl Grignard reagents in asymmetric 1,4-conjugation reactions and provides a direct method to incorporate quaternary chiral centers toward the synthesis of biologically relevant chromanone derivatives.
基金financially supported by the Fundamental Research Funds for the Central Universities,Southwest University for Nationalities (No.12NZYTH03)the Natural Science Foundation of Southwest University for Nationalities (No.381010)+1 种基金the Project of Postgraduate Degree Construction,Southwest University for Nationalities (No.2013XWD-S0703)the State Administration of Foreign Experts Affairs project (No.2012-10)
文摘We describe a convenient method for the synthesis of 1,2-disubstituted acetylenes via a cross-coupling reaction of （bromoethynyl）benzene with Grignard reagents. The reaction of （bromoethynyl）benzene （1 mmol） with Grignard reagent （1.3 mmol） mediated by NiCl2 （4 mol%） and （p-CH3Ph）3P （8 mol%） in THF could produce 1,2-disubstituted acetylenes in good yields at room temperature.
基金This work was supported by the NNSFC (No.29672004).
文摘1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of preparing fused heterocyclic compounds was offered by 1,3-dipolar cycloaddition reaction of silyl nitronates to 1.
文摘Polymeric Grignard Reagent (PGR) based on the chloromethylated poly(ST-co-DVB) resinhas been prepared by means of anthracene-magnesium complex in THF (Anth-Mg-THF), andpolymer matrix with long polymethylene spacer was synthesized via the coupling reaction betweenPGR and α, ω-dibromoalkanes. Based on the studies of factors affecting the coupling, such ascatalyst,reaction time,the length of spacer etc.,this paper offers the optimal reaction conditionsand three typical experiment procedures. The mechanism for the formation and coupling reactionof PGR are also discussed.
文摘l-α-biaomo-2,3,4,6-tetra-O-acetyl-D-giucopyranose reacts with Grignard eagents prepared frorn the acnvated magnesium under very mild condition to ellord C- glucosides in a very high yield compared with Grignard Reagent prepared from usual method.β-anomer predominates in the reaction, mixture The configuration of anomers was assigned by 13C NMR spectra.
基金Supported by the National Natural Science Foundation of China Youth Foundation of Tianjin
文摘The present paper narrates the addition of 5-trimethylsilylcyclohex-3-enone to Grig-nard reagent to give 1-substituted 5-trimethylsilylcyclohex-3-enol in a good yield. The stereochemistry of the addition reaction and their products are discussed.
文摘Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(PPh3)4 to afford (Z)-1,2-disubstituted vinylselenides 3, which were cross-coupled with Grignard reagents in the presence of (PPh3)2NiCl2 to give trisubstituted alkenes 4 stereoselectively in good yields.
基金We are grateful to the National Natural Science Foundation of China(Project No.20332060)the CAS Academician Foundation of Zhejiang Province.
文摘Polymer-supported selenovinyl bromide, easily prepared from polymer-supported selenenyl bromide with acetylene, reacts with different Grignard reagents using a step-by-step strategy to obtain （E）-1, 2-disubstituted ethenes in good yields.
基金funding support from National Natural Science Foundation of China(NSFC,Nos.22271286 and 21971236)the Haixi Institute of CAS(No.CXZX-2017-P01)。
文摘The precise synthesis of polymer with narrow molecular weight distribution(?)and well-defined architectures is very essential to exploring the functions and properties of polymer materials.Here,a universal polymerization method capable of low?and reactive hydrogen compatibility is reported by introducing super-Grignard reagents(R_(2)Mg?Li Cl)into polymer chemistry.Under mild conditions,various monomers,including nonpolar polystyrene and 4-methoxystyrene that cannot be initiated by Grignard reagents,and polar methacrylate,are successfully polymerized with full monomer conversion and low?.This approach is amenable to wide varieties of initiators,polymerization temperature,and feed ratio,which makes it attractive for applications in polymer synthesis.By adding methanol and water during the polymerization process,the reactive hydrogen compatibility of this method is confirmed,which makes this method avoid the rigorous restriction on polymerization conditions of anionic polymerization.Moreover,chain extension polymerization and block copolymerization are achieved and demonstrate the livingness of chain propagation,enabling the facile synthesis of well-defined macromolecular architectures.This work therefore expands the methodology libraries of living polymerization,which may cause inspirations to polymer science.
基金This work was supported by the National NatUral Science Foundation of China the Provincial Natural Science Foundation of Sha
文摘The reaction of 2-substituted imidazolinium salt with bis-Grignard reagents is reported and a new method for the synthesis of symmetric diketones from carboxylic acids and bis-Grignard reagents is provided.
文摘Cyclododecanedione and 1, 8-cyclotetradecanedione were prepared from bis-Grig- nard reagent and dinitriles. This is a convenient synthetic method for large-ring cycloalkanediones.
基金supported by the National Natural Science Foundation of China(22171174)the Fundamental Research Funds for the Central Universities(GK202304033,GK202406026)+2 种基金the Innovation Capability Support Program of Shaanxi(2023-CX-TD-28)the Shaanxi Fundamental Science Research Project for Chemistry&Biology(22JHZ002)the Natural Science Foundation of Shaanxi Province(2023-JC-YB-100).
文摘Arylamines constitute a fundamental class of organic compounds critical to pharmaceuticals,dyes,and advanced materials.The direct synthesis of arylamines from nitro compounds demonstrates significant advantages in step economy,cost efficiency,and functional group compatibility.However,conventional methodologies frequently necessitate transition metal catalysts or excessive reducing agents,limiting their practical applicability.Herein,we introduce a highly efficient photochemical protocol for the synthesis of arylamines from readily accessible nitro compounds and Grignard reagents under purple light(390—395 nm)irradiation,eliminating the requirement for transition metal catalysts or external reducing agents.This protocol exhibits exceptional tolerance to sterically hindered substrates and sensitive functional groups.Preliminary mechanistic investigations suggest the involvement of nitrosoarenes and diarylamine nitrogen radicals as key intermediates in the reaction pathway.
基金the National Natural Science Foundation of China(No.22071107)the Natural Science Foundation of Jiangsu Province,China(No.BK20211588)+2 种基金Provincial Key Research and Development Program of Jiangsu(Modern Agriculture)(No.BE2023333)The Natural Science Foundation of Hebei Province(C2023204011)PJW acknowledges the US NSF(No.CHE-2154593).
文摘Indoles are essential heterocycles in natural products,biological chemistry,and medicinal chemistry.Efficient approaches to their synthesis,therefore,remain in demand.Herein is reported a novel and scalable method to produce a wide variety of indoles by combining Grignard reagents and 2-fluorobenzyl cyanides(59 examples,45%-95%yields).The Grignard reagent adds to the nitrile to give a metalated imine that undergoes S_(N)Ar with unactivated C-F bonds.This strategy installs the R group of RMgX at the indole 2-position,and it is noteworthy that a diverse array of Grignard reagents(aryl,alkyl,vinyl,and cyclopropyl)provide the desired heterocyclic products.The resulting N-magnesiated indole can be in situ functionalized at the 3-position with alkyl halides or functionalized on the nitrogen with silyl chlorides.This method enables the synthesis of indoles with functional groups at each position of the indole backbone(C4-C7),providing handles for further functionalization.
基金This work was financially supported by the National Natural Science Foundation of China （Nos. 21272129 and 21372133） and ＂111＂ Project of Ministry of Educa- tion of China （No. B06005）. We also thank Prof. Er-Cai Shang and Dr. Yan-Jun Guo for their kind advices.
文摘The structure of osthole has been modified to improve its larvicidal activity against mosquitoes. A new efficient synthesis of osthole derivatives with Grignard reagents has been developed, which employs CuI and LiCI as pro- moters and covers a broad range of substrates to afford the corresponding products in mild to good yields （up to 83%）. Bio-activity evaluation showed that several products exhibited better activities than osthole.
基金Project supported by the National Natural Science Foundation of China （No. 20572124）.
文摘Alkyl sulfoxides were synthesized in good yields from the reaction of alkanesulfinyl chloride with Grignard reagents in the presence of zinc chloride.
文摘Diethyl (1-cyanoethyl) phosphorate 1 was reacted with n-butyl-lithium in tetrahydrofuran (THF) at - 78 °C and the resulting carbanion 2 reacted with perfluoroalkanoic add anhydride to afford perfluoroacylated phosphorate 3. Without isolation 3 was attacked by Grignard reagents giving perfluoroalkylated α, β-unsaturated nitriles in 46%-88% yields with high Z-stereoselectivity (Z: E = 89–62:11–38).
基金supported by the National Natural Science Foundation of China (20772089)the Key Laboratory of Organic Chemistry of Jiangsu Provincethe Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘1,3-Bis(2,6-diisopropylphenyl)imidazolium chloride, [DIPrim]Cl, was used to produce a novel iron(III)-containing imidazolium salt [DIPrim][FeCl 4 ], which included a N,N-diarylimidazolium cation (R = 2,6-diisopropylphenyl), [DIPrim] + , and tetrachloroferrate(III) anion, [FeCl 4 ]. This compound was an effective and easy-to-use catalyst for the cross-coupling of aryl Grignard reagents with primary and secondary alkyl halides bearing -hydrogens. After simply decanting the cross-coupling product in the ether layer, [DIPrim][FeCl 4 ] could be reused in at least four successive runs without significant loss of catalytic activity.
基金Project supported by the Provincial Natural Science Foundation of Shaaxi Province
文摘A new synthetic method of ketones from substituted benzimidazolium salts and Grignard reagents is reported. The influences of the various Grignard reagents on the yield of ketones and the mechanism are discussed.
基金supported by the National Natural Science Foundation of China (21172164)the Key Laboratory of Organic Chemistry of Jiangsu Provincethe Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘A series of iron(III)-containing imidazolium salts of the general formula [DRim][FeX 4 ] (R=2,6-diisopropylphenyl, IPr, X=Cl, 1; R=IPr, X=Br, 2; R=tertbutyl, t Bu, X=Cl, 3; R=isopropyl, i Pr, X=Cl, 4; R=benzyl, Bn, X=Cl, 5; R=Bn, X=Br, 6) have been prepared in high yields via reactions of anhydrous ferric halides with equivalent of the corresponding N,N-dihydro- carby-limidazolium halides, where 2-6 are novel ones. All of the complexes were characterized by elemental analysis, Raman spectroscopy, electrospray ionization mass spectroscopy, and X-ray crystallography for 1 and 2. All of them were non-hygroscopic and air-stable, with four of them existing as solids (1-4) and two as liquids (5 and 6) at room temperature. A preliminary catalytic study on the coupling of 4-tolylmagnesium bromide with cyclohexyl bromide revealed that 1 and 3 possessed the highest activity. In comparison, 2, 4 and 5 exhibited moderate activity and the least active complex was 6.
基金supported by the National Natural Science Foundation of China(Grant No.20172041)the Provincial Natural Science Foundation of Shaanxi Province(Grant No.2003B12).
文摘A facile and efficient method for the formylation of Grignard reagent was reported, and a new approach for the preparation of aldehydes from Grignard reagent and benzimidazolium salts was provided.
