<span style='font-family:Verdana;font-size:12px;'>The medicinal uses and applications of metal complexes are of increasing clinical and commercial importance;this is as a result of some level of success ...<span style='font-family:Verdana;font-size:12px;'>The medicinal uses and applications of metal complexes are of increasing clinical and commercial importance;this is as a result of some level of success </span><span style='font-family:Verdana;font-size:12px;'>achieved so far. In this regard, novel enamine free-base ligands were synthesized</span><span style='font-family:Verdana;font-size:12px;'> by the condensation of terephthalaldehyde and 2-(methylamino)ethanol. This afforded a dinegative </span><i><span style='font-family:Verdana;font-size:12px;'>ONNO</span></i><span style='font-family:Verdana;font-size:12px;'> donor enamine, free base, characterized using </span><sup><span style='font-family:Verdana;font-size:12px;'>1</span></sup><span style='font-family:Verdana;font-size:12px;'>H and </span><sup><span style='font-family:Verdana;font-size:12px;'>13</span></sup><span style='font-family:Verdana;font-size:12px;'>C NMR, Fourier-transformed infrared and UV-vis spectroscopy. Coordination compounds of the enamine were also synthesized using Cu(II), Ni(II), Co(II) and VO(IV) ions. These complexes were characterized by electronic, IR spectrophotometry, mass spectrometry, magnetic susceptibility and </span><span style='font-family:Verdana;font-size:12px;'>E</span><span style='font-family:Verdana;font-size:12px;'>DX. The compounds were thereafter evaluated for their antimicrobial and cytotoxic activities. The data obtained w</span><span style='font-size:12px;font-family:Verdana;'>ere</span><span style='font-size:12px;font-family:Verdana;'> supportive of a</span><span style='font-size:12px;font-family:Verdana;'>n</span><span style='font-size:10.0pt;font-family:''><span style='font-family:Verdana;font-size:12px;'> octahedral geometry</span><span style='font-family:Verdana;font-size:12px;'> for the Cu(II) complex, a square-pyramidal geometry for the vanadium complex and a 4-coordinate square-planar geometry for both the cobalt and nickel complexes. The magnetic susceptibility data revealed that the complexes are magnetically dilute and mononuclear with exception of the cobalt complex. The ligands and the complexes did not exhibit significant antimicrobial and cytotoxic assays, indicative of the nontoxicity of the ligand and complexe</span><span style='font-family:Verdana;font-size:12px;'>s.</span></span>展开更多
Many proline-catalyzed asymmetric addition reactions with ketones as substrates were assumed to involve a key intermediate, an enamine, produced by the condensation of proline and ketone. In this paper, the key interm...Many proline-catalyzed asymmetric addition reactions with ketones as substrates were assumed to involve a key intermediate, an enamine, produced by the condensation of proline and ketone. In this paper, the key intermediate enamines derived from L-proline and cyclohexanone (or acetone) as well as the corresponding oxazolidinone and imine tautomers have been investigated by means of density functional calculations at the B3LYP/6-311+G^** level. The predicted order of stability for these tautomers is oxazolidinones 〉 enamines 〉 imines in gas phase and oxazolidinones 〉 imines 〉 enamines in aprotic THF solvent. This prediction explains why enamine intermediate can not be observed experimentally. The predicted energy/enthalpy difference between the formal oxazolidinone structure and the zwitterionic imine structures is very small in THF solvent, suggesting the oxazolidinone-to-imine tautomerization can be readily induced in solvent. ^13C NMR chemical shifts of the oxazolidinone and imine structures have been computed and used to explain the experimental NMR spectra observed in oxazolidinone-to-imine tautomerization induced by protic solvent.展开更多
Compound 5-methyl-2-phenyl-4-[(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one (C24H21N3O) crystallizes in the triclinic system, space group P1, with a = 9.267(3), b = 9.904(4),c = 12.035(4) A°, α ...Compound 5-methyl-2-phenyl-4-[(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one (C24H21N3O) crystallizes in the triclinic system, space group P1, with a = 9.267(3), b = 9.904(4),c = 12.035(4) A°, α = 97.896(6), β = 103.865(6), γ = 107.950(6)°, Mr= 367.44, Z = 2, V = 993.2(6)A°^3,Dc = 1.229 g/cm^3,μ(MoKa) = 0.077 mm^-1 and F(000) = 388. The structure was refined to R =0.0444 and wR = 0.1199 for 2903 observed reflections (I 〉 2σ(I)). The results of ^1H NMR and single-crystal X-ray diffraction studies showed the enamine character of the compound. The strong intramolecular hydrogen bonds in the large conjugate system, together with weak intermolecular C-H……π hydrogen bonding and π……π stacking, lead to the formation of a multi-dimensional supramolecular network.展开更多
An efficient, atom-economic and green approach to synthesizing enamines was developed by intermolecular hydroamination of activated alkynes with high yields under catalyst- and solvent-free conditions. β-Dimethylamin...An efficient, atom-economic and green approach to synthesizing enamines was developed by intermolecular hydroamination of activated alkynes with high yields under catalyst- and solvent-free conditions. β-Dimethylamino-acrylate derivatives were also obtained with high yields. In the synthetic process of the derivatives, N,N-dimethylformamide(DMF) pretreated with metal Na, was used as reactant instead of dimethylamine gas. The proposed synthetic method can be used for the synthesis of (E)-ethyl-3-(dimethylamino)acrylate(3cl), and provide a new possible way to the synthesis of Quinolones.展开更多
The reaction of methyl α-diazoacetoacetate with enamines catalyzed by dirhodium and copper complexes un-derwent formal 1,3-dipolar addition to give 5-amino-4,5-dihydrofurans in moderate yields. The reaction was sug-g...The reaction of methyl α-diazoacetoacetate with enamines catalyzed by dirhodium and copper complexes un-derwent formal 1,3-dipolar addition to give 5-amino-4,5-dihydrofurans in moderate yields. The reaction was sug-gested to proceed via a nucleophilic addition of enamines to metal-carbenes and a subsequent intramolecular cycli-zation of the resulting zwitterionic intermediates.展开更多
A new method for the synthesis of functional enamines from β,β-dicyanostyrene derivatives and N-bromosaccharin(NBSA) was developed. In the presence of Na2CO3, the the reaction of β,β-dicyanostyrene derivatives w...A new method for the synthesis of functional enamines from β,β-dicyanostyrene derivatives and N-bromosaccharin(NBSA) was developed. In the presence of Na2CO3, the the reaction of β,β-dicyanostyrene derivatives with NBSA can generate the corresponding enamines smoothly in a mixed solvent of dichloromethane and N,N-dimethylformamide(DMF)(volume ratio 1:1) at 50 ℃. The reaction of 14 kinds of β,β-dicyanostyrene derivatives with NBSA was investigated. Screened olefins afforded the corresponding enamines in good to excellent yields(up to 94%), indicating that the method has a wide adaptability for the substrate. The catalyst used is inexpen- sive and stable for storage. The amino groups of all products in their structures are on the a-position of products, revealing the reaction has an excellent regioselectivity. The possible pathway involving aminobromination of β,βdicyanostyrene derivative with NBSA first and then elimination of HBr process in one pot has been proposed. The structures of all products were confirmed by ^1H NMR, ^13C NMR and HRMS analysis.展开更多
Asymmetric catalytic hydrogenations of imines and enamines with chiral transition-metal complexes bearing chiral ligands are among the most green and powerful approaches for the elaboration of chiral amine structures ...Asymmetric catalytic hydrogenations of imines and enamines with chiral transition-metal complexes bearing chiral ligands are among the most green and powerful approaches for the elaboration of chiral amine structures in organic synthesis.This review focuses on recent applications of asymmetric hydrogenations of imine and enamine substrates in the total syntheses of natural products.These applications include diverse processes involving asymmetric transfer hydrogenation(ATH)and asymmetric hydrogenation(AH)to form key chiral amine motifs in natural products with good efficiency and high-level enantiocontrol.展开更多
The reactions of enamines (1a–b, 4, 6) with fluorinated acyl chlorides (2a–d ) produced fluorinated 1,3-diketones (3a–f) and 1,3-keto-aldehydes (7a–c) in good yields as well as byproducts fluorinated acylamides (5...The reactions of enamines (1a–b, 4, 6) with fluorinated acyl chlorides (2a–d ) produced fluorinated 1,3-diketones (3a–f) and 1,3-keto-aldehydes (7a–c) in good yields as well as byproducts fluorinated acylamides (5a–c). It is proposed that the reactions involve nucleophilic attack by the C-atom and/or N-atom of the enamines on acyl carbon of the fluorinated acyl chlorides.展开更多
Synthesis of 4'-methoxyflavone, first by the reaction of 4 - methoxy acetophenone enamine with heptanedioyl chloride, then by dehydrogenation, is described.
1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2, Mr = 472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol, and determined by X-ray structu...1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2, Mr = 472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol, and determined by X-ray structure analysis. It crystallizes in the orthorhombic system, space group P21/c with a = 7.9839(16), b = 12.910(3), c = 12.358(3)A, α = 90.00, β= 93.71(3),γ = 90.00°, V = 1271.1(4) A3, Z = 2, Dc = 1.235 g/cm^3,/1 = 0.077 mm^-1, F(000) = 500, the final R = 0.0717 and wR = 0.1187. It presents a linear centrosymmetric framework constituted by a linkage of benzidine as a bridge and two terminal 1-phenyl-1,3-butanedione moieties.展开更多
To investigate the structural form of gossypol and gossypolone Schiff's bases, seven relevant Schiff's bases were synthesized and the electrospray ionization-tandem mass spectrometry (ESI-MS/MS) with low-energy co...To investigate the structural form of gossypol and gossypolone Schiff's bases, seven relevant Schiff's bases were synthesized and the electrospray ionization-tandem mass spectrometry (ESI-MS/MS) with low-energy collision-induced dissociation was used to analyze their fragmentations. A common fragmentation pathway with the loss of RNH2 from those schiff's bases quasi-molecular ions was observed and proposed on the basis of their MS/MS spectra data. This common pathway indicated that those Schiff's bases existed mainly as the enamine form not the imine form previously showed in most reports.展开更多
What is the most favorite and original chemistry developed in your researchgroup?I hope it's always the next one.How do you get into this specific field?Could you please share some experiences with ourreaders?Natu...What is the most favorite and original chemistry developed in your researchgroup?I hope it's always the next one.How do you get into this specific field?Could you please share some experiences with ourreaders?Nature provides many astonishing catalytic machineries for building up molecular complexity and harnessing energy in the most efficient ways.Nature's recipe for catalysis serves as a starting point to develop new catalyst for synthetic and energy chemistry.展开更多
A 5πe carbonyl activation mode is reported on the basis of photo-induced single-electron-transfer (SET) oxidation of a secondary enamine. The resultant β-enaminyl radical intermediate was trapped by a wide range o...A 5πe carbonyl activation mode is reported on the basis of photo-induced single-electron-transfer (SET) oxidation of a secondary enamine. The resultant β-enaminyl radical intermediate was trapped by a wide range of Michael acceptors, producing β-alkylation products of β-ketocarbonyls in a highly efficient manner,展开更多
A simple primary-tertiary diamine has been explored as a novel catalyst for the Morita-Baylis-Hillman reaction of MVK and aryl aldehydes, and moderate to good chemical yields were obtained. Detailed mechanism study in...A simple primary-tertiary diamine has been explored as a novel catalyst for the Morita-Baylis-Hillman reaction of MVK and aryl aldehydes, and moderate to good chemical yields were obtained. Detailed mechanism study indicated that the diamine acted as a bifunctional cooperation catalyst via a bicyclic enamino-quaternary ammonium intermediate.展开更多
The multicomponent reactions of aldehydes,electron deficient alkynes and amines have been successfully per-formed to yield a number of symmetrical 2,6-unsubstituted 1,4-dihydropyridines(1,4-DHPs).This method has been ...The multicomponent reactions of aldehydes,electron deficient alkynes and amines have been successfully per-formed to yield a number of symmetrical 2,6-unsubstituted 1,4-dihydropyridines(1,4-DHPs).This method has been found generally applicable for the synthesis of both N-substituted and N-unsubstituted 1,4-DHPs by employing secondary amine to activate the alkyne component via enaminoester intermediates.The present method runs through an enamine type activation,which is different from the known approach employing AcOH as solvent.展开更多
A simple and directα-allylic alkylation of unmodified aldehydes with allylic alcohols catalyzed by primary amine/Brønsted acid has been developed.The N,N-dimethylethylenediamine/TfOH was identified as the optima...A simple and directα-allylic alkylation of unmodified aldehydes with allylic alcohols catalyzed by primary amine/Brønsted acid has been developed.The N,N-dimethylethylenediamine/TfOH was identified as the optimal catalyst to promote this transformation via an enamine process in high yields(up to 88%)and with good diastereoselectivities(up to 9∶1).展开更多
基金the National Natural Science Foundation of China(Project No.20072033)Specialized Research Fund for the Doctoral Program of Higher Education of China.
文摘<span style='font-family:Verdana;font-size:12px;'>The medicinal uses and applications of metal complexes are of increasing clinical and commercial importance;this is as a result of some level of success </span><span style='font-family:Verdana;font-size:12px;'>achieved so far. In this regard, novel enamine free-base ligands were synthesized</span><span style='font-family:Verdana;font-size:12px;'> by the condensation of terephthalaldehyde and 2-(methylamino)ethanol. This afforded a dinegative </span><i><span style='font-family:Verdana;font-size:12px;'>ONNO</span></i><span style='font-family:Verdana;font-size:12px;'> donor enamine, free base, characterized using </span><sup><span style='font-family:Verdana;font-size:12px;'>1</span></sup><span style='font-family:Verdana;font-size:12px;'>H and </span><sup><span style='font-family:Verdana;font-size:12px;'>13</span></sup><span style='font-family:Verdana;font-size:12px;'>C NMR, Fourier-transformed infrared and UV-vis spectroscopy. Coordination compounds of the enamine were also synthesized using Cu(II), Ni(II), Co(II) and VO(IV) ions. These complexes were characterized by electronic, IR spectrophotometry, mass spectrometry, magnetic susceptibility and </span><span style='font-family:Verdana;font-size:12px;'>E</span><span style='font-family:Verdana;font-size:12px;'>DX. The compounds were thereafter evaluated for their antimicrobial and cytotoxic activities. The data obtained w</span><span style='font-size:12px;font-family:Verdana;'>ere</span><span style='font-size:12px;font-family:Verdana;'> supportive of a</span><span style='font-size:12px;font-family:Verdana;'>n</span><span style='font-size:10.0pt;font-family:''><span style='font-family:Verdana;font-size:12px;'> octahedral geometry</span><span style='font-family:Verdana;font-size:12px;'> for the Cu(II) complex, a square-pyramidal geometry for the vanadium complex and a 4-coordinate square-planar geometry for both the cobalt and nickel complexes. The magnetic susceptibility data revealed that the complexes are magnetically dilute and mononuclear with exception of the cobalt complex. The ligands and the complexes did not exhibit significant antimicrobial and cytotoxic assays, indicative of the nontoxicity of the ligand and complexe</span><span style='font-family:Verdana;font-size:12px;'>s.</span></span>
基金This work was supported by the National Natural Science Foundation of China (No. 20425312)
文摘Many proline-catalyzed asymmetric addition reactions with ketones as substrates were assumed to involve a key intermediate, an enamine, produced by the condensation of proline and ketone. In this paper, the key intermediate enamines derived from L-proline and cyclohexanone (or acetone) as well as the corresponding oxazolidinone and imine tautomers have been investigated by means of density functional calculations at the B3LYP/6-311+G^** level. The predicted order of stability for these tautomers is oxazolidinones 〉 enamines 〉 imines in gas phase and oxazolidinones 〉 imines 〉 enamines in aprotic THF solvent. This prediction explains why enamine intermediate can not be observed experimentally. The predicted energy/enthalpy difference between the formal oxazolidinone structure and the zwitterionic imine structures is very small in THF solvent, suggesting the oxazolidinone-to-imine tautomerization can be readily induced in solvent. ^13C NMR chemical shifts of the oxazolidinone and imine structures have been computed and used to explain the experimental NMR spectra observed in oxazolidinone-to-imine tautomerization induced by protic solvent.
文摘Compound 5-methyl-2-phenyl-4-[(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one (C24H21N3O) crystallizes in the triclinic system, space group P1, with a = 9.267(3), b = 9.904(4),c = 12.035(4) A°, α = 97.896(6), β = 103.865(6), γ = 107.950(6)°, Mr= 367.44, Z = 2, V = 993.2(6)A°^3,Dc = 1.229 g/cm^3,μ(MoKa) = 0.077 mm^-1 and F(000) = 388. The structure was refined to R =0.0444 and wR = 0.1199 for 2903 observed reflections (I 〉 2σ(I)). The results of ^1H NMR and single-crystal X-ray diffraction studies showed the enamine character of the compound. The strong intramolecular hydrogen bonds in the large conjugate system, together with weak intermolecular C-H……π hydrogen bonding and π……π stacking, lead to the formation of a multi-dimensional supramolecular network.
基金Supported by the National Natural Science Foundation of China(Nos.20902001, 21102001), the Natural Science Foundation of the Educational Department of Anhui Province, China(No.KJ2014A013), the "211" Project of Anhui University(China) and the Doctor Research Start-up Fund of Anhui University(China).
文摘An efficient, atom-economic and green approach to synthesizing enamines was developed by intermolecular hydroamination of activated alkynes with high yields under catalyst- and solvent-free conditions. β-Dimethylamino-acrylate derivatives were also obtained with high yields. In the synthetic process of the derivatives, N,N-dimethylformamide(DMF) pretreated with metal Na, was used as reactant instead of dimethylamine gas. The proposed synthetic method can be used for the synthesis of (E)-ethyl-3-(dimethylamino)acrylate(3cl), and provide a new possible way to the synthesis of Quinolones.
基金Project supported by the National Natural Science Foundation of China (No. 20472061) Suzhou University (No. Q4109308) and the Key Laboratory of Organic Synthesis of Jiangsu Province (No. JSK004).
文摘The reaction of methyl α-diazoacetoacetate with enamines catalyzed by dirhodium and copper complexes un-derwent formal 1,3-dipolar addition to give 5-amino-4,5-dihydrofurans in moderate yields. The reaction was sug-gested to proceed via a nucleophilic addition of enamines to metal-carbenes and a subsequent intramolecular cycli-zation of the resulting zwitterionic intermediates.
基金Supported by the Natural Science Foundation of Shaanxi Province of China(No. 20093M2011), and the Innovation Founda- tion of Postgraduate Cultivation of Shaanxi Normal University of China(No. 2008CXB009).
文摘A new method for the synthesis of functional enamines from β,β-dicyanostyrene derivatives and N-bromosaccharin(NBSA) was developed. In the presence of Na2CO3, the the reaction of β,β-dicyanostyrene derivatives with NBSA can generate the corresponding enamines smoothly in a mixed solvent of dichloromethane and N,N-dimethylformamide(DMF)(volume ratio 1:1) at 50 ℃. The reaction of 14 kinds of β,β-dicyanostyrene derivatives with NBSA was investigated. Screened olefins afforded the corresponding enamines in good to excellent yields(up to 94%), indicating that the method has a wide adaptability for the substrate. The catalyst used is inexpen- sive and stable for storage. The amino groups of all products in their structures are on the a-position of products, revealing the reaction has an excellent regioselectivity. The possible pathway involving aminobromination of β,βdicyanostyrene derivative with NBSA first and then elimination of HBr process in one pot has been proposed. The structures of all products were confirmed by ^1H NMR, ^13C NMR and HRMS analysis.
基金This work was supported by the Fundamental Research Funds for the Central Universities(YJ201805,YJ201864).
文摘Asymmetric catalytic hydrogenations of imines and enamines with chiral transition-metal complexes bearing chiral ligands are among the most green and powerful approaches for the elaboration of chiral amine structures in organic synthesis.This review focuses on recent applications of asymmetric hydrogenations of imine and enamine substrates in the total syntheses of natural products.These applications include diverse processes involving asymmetric transfer hydrogenation(ATH)and asymmetric hydrogenation(AH)to form key chiral amine motifs in natural products with good efficiency and high-level enantiocontrol.
基金Project (No. 29272043) supported by the National Natural Science Foundation of China
文摘The reactions of enamines (1a–b, 4, 6) with fluorinated acyl chlorides (2a–d ) produced fluorinated 1,3-diketones (3a–f) and 1,3-keto-aldehydes (7a–c) in good yields as well as byproducts fluorinated acylamides (5a–c). It is proposed that the reactions involve nucleophilic attack by the C-atom and/or N-atom of the enamines on acyl carbon of the fluorinated acyl chlorides.
文摘Synthesis of 4'-methoxyflavone, first by the reaction of 4 - methoxy acetophenone enamine with heptanedioyl chloride, then by dehydrogenation, is described.
文摘1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2, Mr = 472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol, and determined by X-ray structure analysis. It crystallizes in the orthorhombic system, space group P21/c with a = 7.9839(16), b = 12.910(3), c = 12.358(3)A, α = 90.00, β= 93.71(3),γ = 90.00°, V = 1271.1(4) A3, Z = 2, Dc = 1.235 g/cm^3,/1 = 0.077 mm^-1, F(000) = 500, the final R = 0.0717 and wR = 0.1187. It presents a linear centrosymmetric framework constituted by a linkage of benzidine as a bridge and two terminal 1-phenyl-1,3-butanedione moieties.
文摘To investigate the structural form of gossypol and gossypolone Schiff's bases, seven relevant Schiff's bases were synthesized and the electrospray ionization-tandem mass spectrometry (ESI-MS/MS) with low-energy collision-induced dissociation was used to analyze their fragmentations. A common fragmentation pathway with the loss of RNH2 from those schiff's bases quasi-molecular ions was observed and proposed on the basis of their MS/MS spectra data. This common pathway indicated that those Schiff's bases existed mainly as the enamine form not the imine form previously showed in most reports.
基金references,for their significant contributions to this project and the Natural Science Foundation of China(21861132003,91956000 and 22031006)Tsinghua University Initiative Scientific Research Program for financial support.
文摘What is the most favorite and original chemistry developed in your researchgroup?I hope it's always the next one.How do you get into this specific field?Could you please share some experiences with ourreaders?Nature provides many astonishing catalytic machineries for building up molecular complexity and harnessing energy in the most efficient ways.Nature's recipe for catalysis serves as a starting point to develop new catalyst for synthetic and energy chemistry.
基金We thank the National Natural Science Foundation of China (21390400, 21521002, 21572232 and 21672217) and the Chinese Academy of Sciences (QYZDJ-SSW-SLH023) for financial support. S. L. is supported by National Program of Top-notch Young Profes- sionals.
文摘A 5πe carbonyl activation mode is reported on the basis of photo-induced single-electron-transfer (SET) oxidation of a secondary enamine. The resultant β-enaminyl radical intermediate was trapped by a wide range of Michael acceptors, producing β-alkylation products of β-ketocarbonyls in a highly efficient manner,
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20421202, 20632060 and 20702052)Ministry of Science and Technology of China (Grant No. 2008CB617501 & 2009ZX09501-018), and the Chinese Academy of Sciences
文摘A simple primary-tertiary diamine has been explored as a novel catalyst for the Morita-Baylis-Hillman reaction of MVK and aryl aldehydes, and moderate to good chemical yields were obtained. Detailed mechanism study indicated that the diamine acted as a bifunctional cooperation catalyst via a bicyclic enamino-quaternary ammonium intermediate.
基金The work is financially supported by the National Natural Science Foundation of China(Nos.21102059 and 21202064)a research project from the Department of Education of Jiangxi Province(No.GJJ13245)as well as a program sponsored by Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talents.
文摘The multicomponent reactions of aldehydes,electron deficient alkynes and amines have been successfully per-formed to yield a number of symmetrical 2,6-unsubstituted 1,4-dihydropyridines(1,4-DHPs).This method has been found generally applicable for the synthesis of both N-substituted and N-unsubstituted 1,4-DHPs by employing secondary amine to activate the alkyne component via enaminoester intermediates.The present method runs through an enamine type activation,which is different from the known approach employing AcOH as solvent.
基金This work was supported by the National Natural Science Foundation of China(21390400,21025208 and 21202171)the Ministry of Science and Technology(MoST)(2011CB808600)and the Chinese Academy of Sciences.
文摘A simple and directα-allylic alkylation of unmodified aldehydes with allylic alcohols catalyzed by primary amine/Brønsted acid has been developed.The N,N-dimethylethylenediamine/TfOH was identified as the optimal catalyst to promote this transformation via an enamine process in high yields(up to 88%)and with good diastereoselectivities(up to 9∶1).