A complex, NiL(Phen)2(H2O)5 (Phen=1,10 phenanthroline; L=malonate), has been synthesized and chara-cterized. Single crystal X-ray structural determination has been carried out for the complex, the crystal is triclinic...A complex, NiL(Phen)2(H2O)5 (Phen=1,10 phenanthroline; L=malonate), has been synthesized and chara-cterized. Single crystal X-ray structural determination has been carried out for the complex, the crystal is triclinic system, space group P1 with a=1.042 4(4) nm, b=1.061 2(4) nm, c=1.303 8(5) nm, α=85.784(4)°, β=77.232(3)°, γ=72.879(4)°, Mr=611.24, V=1.344 2(8) nm3, Z=2. In this complex, the central metal Ni(Ⅱ) atom is in distorted octa-hedron coordination environment. The molecule is extended to 2D network by the intermolecular π-π stacking interaction.展开更多
Cu/SiO2 catalysts prepared by the ammonia evaporation method were applied to hydrogenation of diethyl malonate to 1,3‐propanediol. The calcination temperature played an important role in the structural evolution and ...Cu/SiO2 catalysts prepared by the ammonia evaporation method were applied to hydrogenation of diethyl malonate to 1,3‐propanediol. The calcination temperature played an important role in the structural evolution and catalytic performance of the Cu/SiO2 catalysts, which were systematically characterized by N2 adsorption‐desorption, inductively coupled plasma‐atomic emission spectros‐copy, N2O chemisorption, X‐ray diffraction, Fourier transform infrared spectroscopy, H2 tempera‐ture‐programmed reduction, transmission electron microscopy, and X‐ray photoelectron spectros‐copy. When the Cu/SiO2 catalyst was calcined at 723 K, 90.7%conversion of diethyl malonate and 32.3%selectivity of 1,3‐propanediol were achieved. Compared with Cu/SiO2 catalysts calcined at other temperatures, the enhanced catalytic performance of the Cu/SiO2 catalyst calcined at 723 K can be attributed to better dispersion of copper species, larger cupreous surface area and greater amount of copper phyllosilicate, which results in a higher ratio of Cu＋/Cu0. The synergetic effect of Cu0 and Cu＋is suggested to be responsible for the optimum activity.展开更多
A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reacti...A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reaction temperature and different bases on the yield of diethyl malonate are also discussed.展开更多
Myrtoidine and malagashanine,highly complex indole alkaloids,are effective adjuvants in developing cures for plasmodium malaria and potent multi-drug resistant agents.Despite nearly 30 years of progress,myrtoidine and...Myrtoidine and malagashanine,highly complex indole alkaloids,are effective adjuvants in developing cures for plasmodium malaria and potent multi-drug resistant agents.Despite nearly 30 years of progress,myrtoidine and the related family of Malagasy alkaloids still present formidable challenges for synthetic chemists.Here,we developed a diastereoselective[2+2+2]tandem cyclization reaction with alkyl-substituted methylene malonate,enabling highly efficient collective total synthesis of four Malagasy alkaloids from commercially available tryptamines within 10-13 steps.The synthetic strategy included rapid and highly stereoselective assembly of the tetracyclic indoline core containing 5-7 contiguous stereogenic carbon centers,rarely seen in indole alkaloids.Among the four natural products,(±)-myrtoidine,(±)-11-demethoxymyrtoidine,and(±)-12-hydroxymalagashanine were synthesized for the first time,and the work on(±)-malagashanine represented the shortest synthetic route so far.Our current study should enable further explorations of chemical and biological spaces based on myrtoidine,malagashanine,and related natural products.展开更多
Malonate is a high-value chemical that can be used to produce value-added compounds.Due to the toxic by-products and low product yield for malonate production through hydrolysis of cyanoacetic acid,microbial productio...Malonate is a high-value chemical that can be used to produce value-added compounds.Due to the toxic by-products and low product yield for malonate production through hydrolysis of cyanoacetic acid,microbial production methods have attracted significant attention.Previously,theβ-alanine pathway has been engineered in Escherichia coli for malonate production.In this study,theβ-alanine pathway was constructed in Saccharomyces cerevisiae by introducing the heterologous genes of BcBAPAT and TcPAND to convert l-aspartate to malonic semialdehyde,combining with co-expression genes of AAT2 and UGA2 to improve precursor supply and malonate producing.Through delta sequence-based integration of the two heterologous genes,the engineered strain produced with 7.21 mg/L malonate was screened.Further,replaced the succinic semialdehyde dehydrogenase gene UGA2 with yneI from E.coli which was utilized to produce malonate in previous study,increased the malonate titer to 7.96 mg/L in flask culture.Following optimization,fermentation of the final engineered strain in shake flasks yielded a maximum malonate titer of 12.83 mg/L,and this was increased to 91.53 mg/L during fed-batch fermentation in a 5 L bioreactor which increased by two-fold compared with that of the engineered strain overexpressing UGA2.展开更多
Ionic liquids （ILs） based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts （PTCs） for the base-promoted monoalkylatio...Ionic liquids （ILs） based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts （PTCs） for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system （IL-hase） could also be recycled after the extraction of products with ether.展开更多
Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported. Various trans-nitroalkenes reacted with malo...Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported. Various trans-nitroalkenes reacted with malonates affording the desired products in up to 95% yield with excellent enantioselectivities （up to 97% ee）.展开更多
Diethyl malonate being an initial raw material, processed with chlorination-replacement-desalination-vacuum rectification, is used to produce carbonyl diethyl malonate. An experiment for optimization determines that t...Diethyl malonate being an initial raw material, processed with chlorination-replacement-desalination-vacuum rectification, is used to produce carbonyl diethyl malonate. An experiment for optimization determines that the best reaction condition was： （1 reaction for 7 h at 10 ℃ with mole-ratio being 2.4 ＂ 1 between chloride and raw material （diethyl malonate）; （2 reaction for 4.5 h at 118 ℃ with mole-ratio being 1.2 ： 1 between the anhydrous sodium acetate and intermediate I. The final product carbonyl diethyl rnalonate recovery ratio reaches up to as high as 79.12% with a purity of 96.4%, which meets the market requirement. This synthesis technique has the advantages of simple process, moderate reaction conditions, high yield and low cost, being suitable for industrial scale production.展开更多
Introduction 5-Monosubstituted isopropylidene malonates arc important synthetic organic intermediates. Since isopropylidene malonate has a stronger acidity （pK;=4.57）, its direct alkylation with alkyl halides usuall...Introduction 5-Monosubstituted isopropylidene malonates arc important synthetic organic intermediates. Since isopropylidene malonate has a stronger acidity （pK;=4.57）, its direct alkylation with alkyl halides usually gives 5,5-disubstitutcd isopropylidene malonates.展开更多
Lanthanum malonate crystals were grown by single tube ionic diffusion through silica gel. The crystallinity of the grown crystals was analyzed by powder X-ray diffraction studies. Fourier transform infrared spectrosco...Lanthanum malonate crystals were grown by single tube ionic diffusion through silica gel. The crystallinity of the grown crystals was analyzed by powder X-ray diffraction studies. Fourier transform infrared spectroscopy （FTIR） and fourier transform （FT） Raman studies confirmed the presence of functional groups in the title compound. The optical band gap energy of the material was extracted from diffuse reflectance spectrum.展开更多
A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The eff...A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The effects of some reaction parameters such as temperature. CO pressure and the concentrations of catalyst on the yields of dimethyl malonate were discussed. The kinetic data were studied and a possible reaction mechanism was proposed.展开更多
Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol a...Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol at moderate temperature. These compounds were characterized by elemental analysis, UV-VIS, IR spectroscopies and powder X-ray diffraction analyses. Compound (<strong>1</strong>) melts at higher temperature (202°C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">°</span>C). The IR spectra showed typical vibrations related to C=N and C=C, characteristic of pyrazolyl and pyridine ligands.展开更多
Abnormal TAR DNA-binding protein 43 （TDP-43） inclusion bodies can be detected in the degen- erative neurons of amyotrophic lateral sclerosis. In this study, we induced chronic oxidative stress injury by applying mal...Abnormal TAR DNA-binding protein 43 （TDP-43） inclusion bodies can be detected in the degen- erative neurons of amyotrophic lateral sclerosis. In this study, we induced chronic oxidative stress injury by applying malonate to cultured mouse cortical motor neurons. In the later stages of the malonate insult, TDP-43 expression reduced in the nuclei and transferred to the cytoplasm. This was accompanied by neuronal death, mimicking the pathological changes in TDP-43 that are seen in patients with amyotrophic lateral sclerosis. Interestingly, in the early stages of the response to malonate treatment, nuclear TDP-43 expression increased, and neurons remained relatively intact, without inclusion bodies or fragmentation. Therefore, we hypothesized that the increase of nuclear TDP-43 expression might be a pro-survival factor against oxidative stress injury. This hypothesis was confirmed by an in vitro transgenic experiment, in which overexpression of wild type mouse TDP-43 in cultured cortical motor neurons significantly reduced malonate-induced neuronal death. Our findings suggest that the loss of function of TDP-43 is an important cause of neuronal degen- eration, and upregulation of nuclear TDP-43 expression might be neuroprotective in amyotrophic lateral sclerosis.展开更多
A series of malonate derivatives-calix[4]arene conjugates were synthesized through Knoevenagel condensation reaction between formyl-tetrapropoxycalix[4]arene and malonate derivatives. The structures of the resulting m...A series of malonate derivatives-calix[4]arene conjugates were synthesized through Knoevenagel condensation reaction between formyl-tetrapropoxycalix[4]arene and malonate derivatives. The structures of the resulting malonate derivative functionalized calix[4]arenes were characterized by NMR spectroscopy, mass spectrometry and even single crystal X-ray diffraction analysis.展开更多
The title complex {CpEu CH(COOC 2H 5) 2 μ CH(COOC 2H 5) 2 } 2 crystallizes in the triclinic system, space group P1 with unit cell constants a=9.108(1), b=11.580(2), c=11.705(2) , α=70.42(1)...The title complex {CpEu CH(COOC 2H 5) 2 μ CH(COOC 2H 5) 2 } 2 crystallizes in the triclinic system, space group P1 with unit cell constants a=9.108(1), b=11.580(2), c=11.705(2) , α=70.42(1)°, β=73.83(1)°, γ=78.60(1)°, D c =1.602 g/cm 3 , M r=1070.76, V=1109.7(3) 3, Z=1, μ (Mo Kα )=28 66 cm 1 and F(000)=536, T=296K, R=0.028, R w =0.037. The geometry around the Eu ion can be described as a pentagonal bipyramid.展开更多
A general and efficient coupling of aryl bromides with diethyl malonate is presented. The reaction provided the α-arylated diethyl malonates in moderate to good yields with a low loading of CUC12（5%, molar fraction...A general and efficient coupling of aryl bromides with diethyl malonate is presented. The reaction provided the α-arylated diethyl malonates in moderate to good yields with a low loading of CUC12（5%, molar fraction） and 8-hydroxyquinoline（5% , molar fraction）. This method has good compatibility for a wide range of aryl bromides.展开更多
The title complex [CaCo（C3H2O4）2（H2O）4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a...The title complex [CaCo（C3H2O4）2（H2O）4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 14,195（9）, b = 7.708（5）, c = 13.441（8） A, β =119.575（9）°, V = 1279.0（14） A3, Dc= 1.948 g/cm^3,μ=1.803 mm^-1, F（000） = 764 and Z = 4. The final R = 0.0245 and wR = 0.0652 for 1344 observed reflections with I 〉 2σ（I）. The structure of the title complex consists of CaO8 polyhedra and CoO6 octahedra linked together by malonate ligands. The Ca（Ⅱ） cation on a twofold axis is coordinated by two water molecules and six malonate O atoms. The Co（Ⅱ） cation which lies in a centre of symmetry in an octahedral arrangement is coordinated by four malonate O atoms and two water molecules, The structure comprises alternating layers along the [101] plane, with the shortest Co-Co distance of 6.961（5）A. The whole 3D structure is maintained and stabilized by the presence of hydrogen bonds.展开更多
文摘A complex, NiL(Phen)2(H2O)5 (Phen=1,10 phenanthroline; L=malonate), has been synthesized and chara-cterized. Single crystal X-ray structural determination has been carried out for the complex, the crystal is triclinic system, space group P1 with a=1.042 4(4) nm, b=1.061 2(4) nm, c=1.303 8(5) nm, α=85.784(4)°, β=77.232(3)°, γ=72.879(4)°, Mr=611.24, V=1.344 2(8) nm3, Z=2. In this complex, the central metal Ni(Ⅱ) atom is in distorted octa-hedron coordination environment. The molecule is extended to 2D network by the intermolecular π-π stacking interaction.
文摘Cu/SiO2 catalysts prepared by the ammonia evaporation method were applied to hydrogenation of diethyl malonate to 1,3‐propanediol. The calcination temperature played an important role in the structural evolution and catalytic performance of the Cu/SiO2 catalysts, which were systematically characterized by N2 adsorption‐desorption, inductively coupled plasma‐atomic emission spectros‐copy, N2O chemisorption, X‐ray diffraction, Fourier transform infrared spectroscopy, H2 tempera‐ture‐programmed reduction, transmission electron microscopy, and X‐ray photoelectron spectros‐copy. When the Cu/SiO2 catalyst was calcined at 723 K, 90.7%conversion of diethyl malonate and 32.3%selectivity of 1,3‐propanediol were achieved. Compared with Cu/SiO2 catalysts calcined at other temperatures, the enhanced catalytic performance of the Cu/SiO2 catalyst calcined at 723 K can be attributed to better dispersion of copper species, larger cupreous surface area and greater amount of copper phyllosilicate, which results in a higher ratio of Cu＋/Cu0. The synergetic effect of Cu0 and Cu＋is suggested to be responsible for the optimum activity.
文摘A green synthesis route of diethyl malonate by palladium catalyzed carbonylation of ethyl chloroacetate in the presence of phase transfer agent is carried out under mild conditions in good yield. The effects of reaction temperature and different bases on the yield of diethyl malonate are also discussed.
基金This research was made possible as a result of a generous grant from the National Natural Science Foundation of China(NSFC,grant nos.21772224 and 91956103).
文摘Myrtoidine and malagashanine,highly complex indole alkaloids,are effective adjuvants in developing cures for plasmodium malaria and potent multi-drug resistant agents.Despite nearly 30 years of progress,myrtoidine and the related family of Malagasy alkaloids still present formidable challenges for synthetic chemists.Here,we developed a diastereoselective[2+2+2]tandem cyclization reaction with alkyl-substituted methylene malonate,enabling highly efficient collective total synthesis of four Malagasy alkaloids from commercially available tryptamines within 10-13 steps.The synthetic strategy included rapid and highly stereoselective assembly of the tetracyclic indoline core containing 5-7 contiguous stereogenic carbon centers,rarely seen in indole alkaloids.Among the four natural products,(±)-myrtoidine,(±)-11-demethoxymyrtoidine,and(±)-12-hydroxymalagashanine were synthesized for the first time,and the work on(±)-malagashanine represented the shortest synthetic route so far.Our current study should enable further explorations of chemical and biological spaces based on myrtoidine,malagashanine,and related natural products.
基金supported by the National Key R&D Program of China(2019YFA0905502)the National Natural Science Foundation of China(21877053)+1 种基金Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(TSBICIP-KJGG-015)the Open Foundation of Jiangsu Key Laboratory of Industrial Biotechnology(KLIB-KF201807).
文摘Malonate is a high-value chemical that can be used to produce value-added compounds.Due to the toxic by-products and low product yield for malonate production through hydrolysis of cyanoacetic acid,microbial production methods have attracted significant attention.Previously,theβ-alanine pathway has been engineered in Escherichia coli for malonate production.In this study,theβ-alanine pathway was constructed in Saccharomyces cerevisiae by introducing the heterologous genes of BcBAPAT and TcPAND to convert l-aspartate to malonic semialdehyde,combining with co-expression genes of AAT2 and UGA2 to improve precursor supply and malonate producing.Through delta sequence-based integration of the two heterologous genes,the engineered strain produced with 7.21 mg/L malonate was screened.Further,replaced the succinic semialdehyde dehydrogenase gene UGA2 with yneI from E.coli which was utilized to produce malonate in previous study,increased the malonate titer to 7.96 mg/L in flask culture.Following optimization,fermentation of the final engineered strain in shake flasks yielded a maximum malonate titer of 12.83 mg/L,and this was increased to 91.53 mg/L during fed-batch fermentation in a 5 L bioreactor which increased by two-fold compared with that of the engineered strain overexpressing UGA2.
文摘Ionic liquids （ILs） based on 1,3-dialkylimidazolium and tetraalkylammonium cations were employed as a series of efficient, environmentally benign phase-transfer catalysts （PTCs） for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system （IL-hase） could also be recycled after the extraction of products with ether.
基金support from Natural Science Foundation of China(No.20772097)Sichuan Provincial Science Foundation for Outstanding Youth(No.05ZQ026-008)Key Project of the Education Department of Sichuan Province(No.2006A081).
文摘Highly efficient Michael addition reactions of malonates to nitroalkenes catalyzed by novel chiral thioureas derived from optically pure BINOL and amino acids are reported. Various trans-nitroalkenes reacted with malonates affording the desired products in up to 95% yield with excellent enantioselectivities （up to 97% ee）.
基金Supported by the Innovation Fund for Technology Based Firms(10C26224212340)
文摘Diethyl malonate being an initial raw material, processed with chlorination-replacement-desalination-vacuum rectification, is used to produce carbonyl diethyl malonate. An experiment for optimization determines that the best reaction condition was： （1 reaction for 7 h at 10 ℃ with mole-ratio being 2.4 ＂ 1 between chloride and raw material （diethyl malonate）; （2 reaction for 4.5 h at 118 ℃ with mole-ratio being 1.2 ： 1 between the anhydrous sodium acetate and intermediate I. The final product carbonyl diethyl rnalonate recovery ratio reaches up to as high as 79.12% with a purity of 96.4%, which meets the market requirement. This synthesis technique has the advantages of simple process, moderate reaction conditions, high yield and low cost, being suitable for industrial scale production.
基金Supported by the National Natural Science Foundation of Chinathe Basic Research Foundation of Zhejian Educational Commission.
文摘Introduction 5-Monosubstituted isopropylidene malonates arc important synthetic organic intermediates. Since isopropylidene malonate has a stronger acidity （pK;=4.57）, its direct alkylation with alkyl halides usually gives 5,5-disubstitutcd isopropylidene malonates.
文摘Lanthanum malonate crystals were grown by single tube ionic diffusion through silica gel. The crystallinity of the grown crystals was analyzed by powder X-ray diffraction studies. Fourier transform infrared spectroscopy （FTIR） and fourier transform （FT） Raman studies confirmed the presence of functional groups in the title compound. The optical band gap energy of the material was extracted from diffuse reflectance spectrum.
文摘A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The effects of some reaction parameters such as temperature. CO pressure and the concentrations of catalyst on the yields of dimethyl malonate were discussed. The kinetic data were studied and a possible reaction mechanism was proposed.
文摘Two novel copper complexes (<strong>1,2</strong>) with N,O-donor ligands were synthesized by reaction of copper(II) malonates with 3,3’-bis(pyrazolyl)pentane and 4,4’-trimethylenedipyridine in methanol at moderate temperature. These compounds were characterized by elemental analysis, UV-VIS, IR spectroscopies and powder X-ray diffraction analyses. Compound (<strong>1</strong>) melts at higher temperature (202°C) than compound (<strong>2</strong>) (100<span style="white-space:normal;">°</span>C). The IR spectra showed typical vibrations related to C=N and C=C, characteristic of pyrazolyl and pyridine ligands.
基金supported by the State Key Program of the Natural Science Foundation of China,No.81030019the National Science Foundation for Young Scholars of China,No.81200969the Peking University Third Hospital Scientific Research Foundation for Returned Scholars,No.73526-01
文摘Abnormal TAR DNA-binding protein 43 （TDP-43） inclusion bodies can be detected in the degen- erative neurons of amyotrophic lateral sclerosis. In this study, we induced chronic oxidative stress injury by applying malonate to cultured mouse cortical motor neurons. In the later stages of the malonate insult, TDP-43 expression reduced in the nuclei and transferred to the cytoplasm. This was accompanied by neuronal death, mimicking the pathological changes in TDP-43 that are seen in patients with amyotrophic lateral sclerosis. Interestingly, in the early stages of the response to malonate treatment, nuclear TDP-43 expression increased, and neurons remained relatively intact, without inclusion bodies or fragmentation. Therefore, we hypothesized that the increase of nuclear TDP-43 expression might be a pro-survival factor against oxidative stress injury. This hypothesis was confirmed by an in vitro transgenic experiment, in which overexpression of wild type mouse TDP-43 in cultured cortical motor neurons significantly reduced malonate-induced neuronal death. Our findings suggest that the loss of function of TDP-43 is an important cause of neuronal degen- eration, and upregulation of nuclear TDP-43 expression might be neuroprotective in amyotrophic lateral sclerosis.
基金Financial support from the National Natural Science Foundation of China (No. 21371177) is acknowledged
文摘A series of malonate derivatives-calix[4]arene conjugates were synthesized through Knoevenagel condensation reaction between formyl-tetrapropoxycalix[4]arene and malonate derivatives. The structures of the resulting malonate derivative functionalized calix[4]arenes were characterized by NMR spectroscopy, mass spectrometry and even single crystal X-ray diffraction analysis.
文摘The title complex {CpEu CH(COOC 2H 5) 2 μ CH(COOC 2H 5) 2 } 2 crystallizes in the triclinic system, space group P1 with unit cell constants a=9.108(1), b=11.580(2), c=11.705(2) , α=70.42(1)°, β=73.83(1)°, γ=78.60(1)°, D c =1.602 g/cm 3 , M r=1070.76, V=1109.7(3) 3, Z=1, μ (Mo Kα )=28 66 cm 1 and F(000)=536, T=296K, R=0.028, R w =0.037. The geometry around the Eu ion can be described as a pentagonal bipyramid.
基金Supported by the National Natural Science Foundation of China（Nos.21572215, 21602215）.
文摘A general and efficient coupling of aryl bromides with diethyl malonate is presented. The reaction provided the α-arylated diethyl malonates in moderate to good yields with a low loading of CUC12（5%, molar fraction） and 8-hydroxyquinoline（5% , molar fraction）. This method has good compatibility for a wide range of aryl bromides.
基金This work was supported by the Education Office of Anhui Province (No. 200161) and the Hubei Key Laboratory of Novel Chemical Reactor and Green Chemical Technology (No. RCT2004011)
文摘The title complex [CaCo（C3H2O4）2（H2O）4]n with a formula of C6HI2CaCoO12 and Mr=375.17 has been synthesized and structurally characterized by X-ray diffraction. The crystal is of monoclinic, space group C2/c with a = 14,195（9）, b = 7.708（5）, c = 13.441（8） A, β =119.575（9）°, V = 1279.0（14） A3, Dc= 1.948 g/cm^3,μ=1.803 mm^-1, F（000） = 764 and Z = 4. The final R = 0.0245 and wR = 0.0652 for 1344 observed reflections with I 〉 2σ（I）. The structure of the title complex consists of CaO8 polyhedra and CoO6 octahedra linked together by malonate ligands. The Ca（Ⅱ） cation on a twofold axis is coordinated by two water molecules and six malonate O atoms. The Co（Ⅱ） cation which lies in a centre of symmetry in an octahedral arrangement is coordinated by four malonate O atoms and two water molecules, The structure comprises alternating layers along the [101] plane, with the shortest Co-Co distance of 6.961（5）A. The whole 3D structure is maintained and stabilized by the presence of hydrogen bonds.
