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2016 Volume 36 Issue 10
2016, 36(10): 2249-2271
doi: 10.6023/cjoc201609005
Abstract:
The Cu-catalyzed asymmetric addition of borons to olefins is an efficient method to the construct chiral C-B bonds and has therefore gained much attention over recent years. This review describes recent research progress concerning Cu-catalyzed asymmetric additions of borons to olefins on the view of the types of olefin substrates and reactions. Such reactions include hydroborations, cascade reactions, difunctionalization reactions, and their associated mechanisms and developments. Additionally, research trends of this area are also discussed.
The Cu-catalyzed asymmetric addition of borons to olefins is an efficient method to the construct chiral C-B bonds and has therefore gained much attention over recent years. This review describes recent research progress concerning Cu-catalyzed asymmetric additions of borons to olefins on the view of the types of olefin substrates and reactions. Such reactions include hydroborations, cascade reactions, difunctionalization reactions, and their associated mechanisms and developments. Additionally, research trends of this area are also discussed.
2016, 36(10): 2272-2283
doi: 10.6023/cjoc201606015
Abstract:
Since the 1980 s, organic electronics had made great progress. Organic semiconductors have attracted much attention of scientists from both academy and industry due to their promising applications in low-cost, lightweight, flexible and solution-processable electronics. The development of the third-generation donor-acceptor (D-A) polymers greatly improved the device performance of organic semiconductors. Recently, isoindigo-based polymers develop rapidly, especially as organic field-effect transistors (OFETs) materials, and high hole mobilities up to 3.62 cm2·V-1·s-1 for IID and 14.4 cm2·V-1·s-1 for its derivatives, were successfully achieved. In this review, the recent advance in isoindigo-based polymer field-effect transistor materials is summarized, which focus on the molecular design and synthesis, device fabrication and structure-property rela-tionship study of isoindigo-based polymers, aiming to providing valuable information for the materials exploitation in the future.
Since the 1980 s, organic electronics had made great progress. Organic semiconductors have attracted much attention of scientists from both academy and industry due to their promising applications in low-cost, lightweight, flexible and solution-processable electronics. The development of the third-generation donor-acceptor (D-A) polymers greatly improved the device performance of organic semiconductors. Recently, isoindigo-based polymers develop rapidly, especially as organic field-effect transistors (OFETs) materials, and high hole mobilities up to 3.62 cm2·V-1·s-1 for IID and 14.4 cm2·V-1·s-1 for its derivatives, were successfully achieved. In this review, the recent advance in isoindigo-based polymer field-effect transistor materials is summarized, which focus on the molecular design and synthesis, device fabrication and structure-property rela-tionship study of isoindigo-based polymers, aiming to providing valuable information for the materials exploitation in the future.
2016, 36(10): 2284-2300
doi: 10.6023/cjoc201604019
Abstract:
Organic solar cell (OSC) is a kind of solar cells which active layer is made of organic materials. Ben-zo[1,2-b:4,5-b']dithiophene (BDT) has become a star molecule unit in organic solar cells donor material field, because its large rigid plane conjugated structure can improve the delocalization of π-electron and π-π interactions between molecules significantly. BDT is also easy to be synthesized and chemically modified. The highest power conversion efficiency (PCE) 9.95% has already been achieved based on BDT unit, which shows an enormous potential application in organic photovoltaic device (OPV). This paper summarizes the research process of BDT-based small molecule organic solar cell (SM-OSC) active layer material in recent years and gives a brief analysis of device performance effects caused by main chain, side chain and terminal group of small mol-ecule.
Organic solar cell (OSC) is a kind of solar cells which active layer is made of organic materials. Ben-zo[1,2-b:4,5-b']dithiophene (BDT) has become a star molecule unit in organic solar cells donor material field, because its large rigid plane conjugated structure can improve the delocalization of π-electron and π-π interactions between molecules significantly. BDT is also easy to be synthesized and chemically modified. The highest power conversion efficiency (PCE) 9.95% has already been achieved based on BDT unit, which shows an enormous potential application in organic photovoltaic device (OPV). This paper summarizes the research process of BDT-based small molecule organic solar cell (SM-OSC) active layer material in recent years and gives a brief analysis of device performance effects caused by main chain, side chain and terminal group of small mol-ecule.
2016, 36(10): 2301-2316
doi: 10.6023/cjoc201603006
Abstract:
Synthesis and application of chiral phosphine ligand is an important research area in the field of asymmetric synthesis. According to the chiral center and the structural characteristics, the recent development of efficient chiral phosphine ligand in asymmetric synthesis is reviewed, and the prospects of chiral phosphine ligand are also discussed.
Synthesis and application of chiral phosphine ligand is an important research area in the field of asymmetric synthesis. According to the chiral center and the structural characteristics, the recent development of efficient chiral phosphine ligand in asymmetric synthesis is reviewed, and the prospects of chiral phosphine ligand are also discussed.
2016, 36(10): 2317-2332
doi: 10.6023/cjoc201604023
Abstract:
Tetraphenylethene derivatives display unique optical and/or electrical properties and biological activity due to their large π-conjugated system, endowing their broad applications in optoelectronic materials, bio-imaging and other areas. Such compounds are facile to synthesize, easy to functionalize and have obvious aggregation induced emission (AIE) effect, thus attracted increasing more attentions and get tremendous development in the past dacades. The recent progress in research of tetraphenylethene derivatives in chemical sensing, biological probes, organic light emitting diodes (OLEDs) and relating areas is reviewed, and its development trend is briefly prospected.
Tetraphenylethene derivatives display unique optical and/or electrical properties and biological activity due to their large π-conjugated system, endowing their broad applications in optoelectronic materials, bio-imaging and other areas. Such compounds are facile to synthesize, easy to functionalize and have obvious aggregation induced emission (AIE) effect, thus attracted increasing more attentions and get tremendous development in the past dacades. The recent progress in research of tetraphenylethene derivatives in chemical sensing, biological probes, organic light emitting diodes (OLEDs) and relating areas is reviewed, and its development trend is briefly prospected.
2016, 36(10): 2333-2343
doi: 10.6023/cjoc201605009
Abstract:
In comparison with the chemical hydration and hydrolysis of nitriles, which usually involves harsh reaction condi-tions and low selectivity, biocatalytic desymmetrizations of prochiral or meso nitriles are highly efficient, highly enantioselective and environmentally benign. Therefore, biocatalysis and biotransformation has offered an attractive and unique protocol for the enantioselective synthesis of polyfunctionalized organic compounds that are not readily obtainable by other methods. This review summarizes the biocatalytic desymmetrization of prochiral nitriles including glutaronitriles, malonitriles and meso cyclic dinitriles during the past two decades.
In comparison with the chemical hydration and hydrolysis of nitriles, which usually involves harsh reaction condi-tions and low selectivity, biocatalytic desymmetrizations of prochiral or meso nitriles are highly efficient, highly enantioselective and environmentally benign. Therefore, biocatalysis and biotransformation has offered an attractive and unique protocol for the enantioselective synthesis of polyfunctionalized organic compounds that are not readily obtainable by other methods. This review summarizes the biocatalytic desymmetrization of prochiral nitriles including glutaronitriles, malonitriles and meso cyclic dinitriles during the past two decades.
2016, 36(10): 2344-2352
doi: 10.6023/cjoc201603048
Abstract:
The metal catalysts based on phosphinoarenesulfonate (PO) ligand display interesting olefin polymerization prop-erties, which not only polymerize ethylene to linear polyethylene, but also copolymerize ethylene with polar vinyl monomers or CO to functional linear copolymers. The structural features of PO ligand and the novel polymerization reactions initiated by (PO)Pd(Ⅱ) complexes are assumed. Then the application of (PO)Ni(Ⅱ) catalysts in the copolymerization of ethylene with polar monomers, as well as the rare catalytic properties of Pd(Ⅱ), Ru(Ⅳ) catalysts based on phosphine-bis(arenesulfonate) (OPO) ligands are reviewed. At last, the influence of PO ligand structural features such as symmetry, flexibility, steric effect in axial direction, as well as the pure electronic effect on the insertion and polymerization reactivity of PO metal catalyst are explored, at the same time, the catalytic reaction mechanism is also studied.
The metal catalysts based on phosphinoarenesulfonate (PO) ligand display interesting olefin polymerization prop-erties, which not only polymerize ethylene to linear polyethylene, but also copolymerize ethylene with polar vinyl monomers or CO to functional linear copolymers. The structural features of PO ligand and the novel polymerization reactions initiated by (PO)Pd(Ⅱ) complexes are assumed. Then the application of (PO)Ni(Ⅱ) catalysts in the copolymerization of ethylene with polar monomers, as well as the rare catalytic properties of Pd(Ⅱ), Ru(Ⅳ) catalysts based on phosphine-bis(arenesulfonate) (OPO) ligands are reviewed. At last, the influence of PO ligand structural features such as symmetry, flexibility, steric effect in axial direction, as well as the pure electronic effect on the insertion and polymerization reactivity of PO metal catalyst are explored, at the same time, the catalytic reaction mechanism is also studied.
2016, 36(10): 2353-2367
doi: 10.6023/cjoc201604053
Abstract:
Ionic liquids (ILs) have been widely used as green reaction solvents and/or catalysts in organic synthesis due to their advantages, including low volatility, good thermal stability, good solubility and recyclability. ILs have played a significant role in accelerating reaction rate and selectivity. The recent advances in the application of ILs as catalysts or solvents are summarized in this review, such as in Baylis-Hillman reaction, Michael addition, oxidation and reduction reaction, Knoevenagel condensation, aldol reaction, Diels-Alder reaction, Heck coupling reaction, Suzuki reaction, asymmetric reaction, Biginelli reaction, Mannich reaction and Hantzsch reaction. Relationship between structure and catalytic efficiency of ILs as well as plausible mechanism has been discussed, which is beneficial to develop the novel task-specific ionic liquids with diverse functionalities.
Ionic liquids (ILs) have been widely used as green reaction solvents and/or catalysts in organic synthesis due to their advantages, including low volatility, good thermal stability, good solubility and recyclability. ILs have played a significant role in accelerating reaction rate and selectivity. The recent advances in the application of ILs as catalysts or solvents are summarized in this review, such as in Baylis-Hillman reaction, Michael addition, oxidation and reduction reaction, Knoevenagel condensation, aldol reaction, Diels-Alder reaction, Heck coupling reaction, Suzuki reaction, asymmetric reaction, Biginelli reaction, Mannich reaction and Hantzsch reaction. Relationship between structure and catalytic efficiency of ILs as well as plausible mechanism has been discussed, which is beneficial to develop the novel task-specific ionic liquids with diverse functionalities.
2016, 36(10): 2368-2379
doi: 10.6023/cjoc201604006
Abstract:
The recent progress in transition metal-catalyzed asymmetric ring-opening reactions of oxa(aza)bicyclic alkenes with carbanion nucleophiles is reviewed with focus on the influence of the types of transition metal catalysts, carbanion nucleophiles, ligands, the structures of oxa(aza)bicyclic alkenes, solvents and additives on the asymmetric ring-opening reactions. Moreover, the parties of possible mechanisms for the asymmetric ring-opening reactions are also discussed.
The recent progress in transition metal-catalyzed asymmetric ring-opening reactions of oxa(aza)bicyclic alkenes with carbanion nucleophiles is reviewed with focus on the influence of the types of transition metal catalysts, carbanion nucleophiles, ligands, the structures of oxa(aza)bicyclic alkenes, solvents and additives on the asymmetric ring-opening reactions. Moreover, the parties of possible mechanisms for the asymmetric ring-opening reactions are also discussed.
2016, 36(10): 2380-2396
doi: 10.6023/cjoc201603031
Abstract:
Spirotryprostatin is one of the alkaloids which contains the spiro-indolyl diketopiperazine structure. It is structurally characterized by indole moiety connected to diketopiperazine moiety via the spiro quaternary carbon chiral center. The combination of the structure of spiro-indoyl and diketopiperazine has demonstrated the special physiological and pharmacological activities, especially the excellent inhibitory activity to cell cycle. In recent years, The synthesis of spirotryprostatin has attracted much attention, according to the formation of the spirocyclic chiral center. The total synthetic efforts towards spirotryprostatin alkaloids are presented.
Spirotryprostatin is one of the alkaloids which contains the spiro-indolyl diketopiperazine structure. It is structurally characterized by indole moiety connected to diketopiperazine moiety via the spiro quaternary carbon chiral center. The combination of the structure of spiro-indoyl and diketopiperazine has demonstrated the special physiological and pharmacological activities, especially the excellent inhibitory activity to cell cycle. In recent years, The synthesis of spirotryprostatin has attracted much attention, according to the formation of the spirocyclic chiral center. The total synthetic efforts towards spirotryprostatin alkaloids are presented.
2016, 36(10): 2397-2406
doi: 10.6023/cjoc201606039
Abstract:
Chiral β-iodo Morita-Baylis-Hillman (MBH) adducts are important versatile synthetic building blocks for many nat-ural products and drug molecules. By using a recently developed acyl transfer catalyst An-PIQ, the kinetic resolutions of a series of β-iodo MBH adducts were investigated, providing the recovered alcohols in good yields with high enantioselectivities (up to 99.9% ee) and good selectivity factors (S up to 165). This method overcomes the issue of low selectivity confronted in the kinetic resolution of aliphatic aldehyde-derived MBH adducts as secondly alcohols, and features mild reaction conditions, broad sub-strate scope, and easy scaling-up to gram scale.
Chiral β-iodo Morita-Baylis-Hillman (MBH) adducts are important versatile synthetic building blocks for many nat-ural products and drug molecules. By using a recently developed acyl transfer catalyst An-PIQ, the kinetic resolutions of a series of β-iodo MBH adducts were investigated, providing the recovered alcohols in good yields with high enantioselectivities (up to 99.9% ee) and good selectivity factors (S up to 165). This method overcomes the issue of low selectivity confronted in the kinetic resolution of aliphatic aldehyde-derived MBH adducts as secondly alcohols, and features mild reaction conditions, broad sub-strate scope, and easy scaling-up to gram scale.
2016, 36(10): 2407-2412
doi: 10.6023/cjoc201606020
Abstract:
Three diamine compounds with an anthracene bridge were synthesized and characterized, including 1,5-bis(di-p-anisylamine)anthracene (1), 2,6-bis(di-p-anisylamine)anthracene (2) and 9,10-bis(di-p-anisylamine)anthracene (3). The elec-trochemistry, absorption and emission spectra, spectroelectrochemistry, and amine-amine electronic coupling of these compounds were examined. All compounds display two consecutive redox couples in the potential region between +0.6 and +1.0 V vs Ag/AgCl, with a potential splitting △E of around 100 mV. In the one-electron-oxidized state, weak intervalence charge transfer (IVCT) transitions were observed for 1·+ in the near-infrared (NIR) region and the electronic coupling parameter Vab was calculated to be 600 cm-1. In contrast, compound 3·+ displays an intense IVCT band in the NIR region with a Vab value of 1440 cm-1. However, no distinct IVCT band was discernable for 2·+, indicative of an eligible electronic coupling. This work demonstrates that the positions of the amine substituents on the anthracene bridge play a critical role in determining the degree of amine-amine electronic coupling.
Three diamine compounds with an anthracene bridge were synthesized and characterized, including 1,5-bis(di-p-anisylamine)anthracene (1), 2,6-bis(di-p-anisylamine)anthracene (2) and 9,10-bis(di-p-anisylamine)anthracene (3). The elec-trochemistry, absorption and emission spectra, spectroelectrochemistry, and amine-amine electronic coupling of these compounds were examined. All compounds display two consecutive redox couples in the potential region between +0.6 and +1.0 V vs Ag/AgCl, with a potential splitting △E of around 100 mV. In the one-electron-oxidized state, weak intervalence charge transfer (IVCT) transitions were observed for 1·+ in the near-infrared (NIR) region and the electronic coupling parameter Vab was calculated to be 600 cm-1. In contrast, compound 3·+ displays an intense IVCT band in the NIR region with a Vab value of 1440 cm-1. However, no distinct IVCT band was discernable for 2·+, indicative of an eligible electronic coupling. This work demonstrates that the positions of the amine substituents on the anthracene bridge play a critical role in determining the degree of amine-amine electronic coupling.
2016, 36(10): 2413-2418
doi: 10.6023/cjoc201604040
Abstract:
A novel fluorescent probe R based on rhodamine B was synthesized by the condensation of rhodamine B hydrazide and phenylglyoxal monohydrate, followed by reduction with NaBH4, and its structure was characterized by 1H NMR, 13C NMR, ESI-MS, elemental analysis, and X-ray single analysis. It exhibited very strong fluorescence responses to Hg2+ with remarkably high selectivity for Hg2+ over other metal ions. When the concentration of Hg2+ was in the range of 5×10-7~2×10-6 mol/L, there was a good linearity between the fluorescence intensity and the concentration of Hg2+. The fluorescence imaging experiments of Hg2+ in MGC-803 living cells revealed its potential application in biological system.
A novel fluorescent probe R based on rhodamine B was synthesized by the condensation of rhodamine B hydrazide and phenylglyoxal monohydrate, followed by reduction with NaBH4, and its structure was characterized by 1H NMR, 13C NMR, ESI-MS, elemental analysis, and X-ray single analysis. It exhibited very strong fluorescence responses to Hg2+ with remarkably high selectivity for Hg2+ over other metal ions. When the concentration of Hg2+ was in the range of 5×10-7~2×10-6 mol/L, there was a good linearity between the fluorescence intensity and the concentration of Hg2+. The fluorescence imaging experiments of Hg2+ in MGC-803 living cells revealed its potential application in biological system.
2016, 36(10): 2419-2425
doi: 10.6023/cjoc201605030
Abstract:
The Cu(I)-catalyzed intramolecular cyclization of ortho-halogenated phenylthioacetamides to form 2-amino ben-zo[b]thiophenes in water was studied. This method employed water instead of organic solvent, and the catalyst-loading can be as low as to 5 mol% and the yield of products is up to 98%, which overcomes the drawbacks such as harsh reaction conditions and low yields in the previous methods. In addition, the reaction can be scaled up to gram-scale and catalyst can be reused with a maintained yield of products. This reaction provided a simple and environmentally friendly protocol for the preparaion of 2-amino benzo[b]thiophene and their derivatives.
The Cu(I)-catalyzed intramolecular cyclization of ortho-halogenated phenylthioacetamides to form 2-amino ben-zo[b]thiophenes in water was studied. This method employed water instead of organic solvent, and the catalyst-loading can be as low as to 5 mol% and the yield of products is up to 98%, which overcomes the drawbacks such as harsh reaction conditions and low yields in the previous methods. In addition, the reaction can be scaled up to gram-scale and catalyst can be reused with a maintained yield of products. This reaction provided a simple and environmentally friendly protocol for the preparaion of 2-amino benzo[b]thiophene and their derivatives.
2016, 36(10): 2426-2436
doi: 10.6023/cjoc201603029
Abstract:
The development of efficient and sustainable methods for the synthesis of thiophene and furan derivatives is an important task because of the central role of this class of compounds in many natural products, pharmaceuticals and designed materials applications. In this work, a highly efficient selective synthesis of 2,5-disubstituted furan, 2,5-disubstituted thiophene derivatives, benzo[b]furan and benzo[b]thiophene derivatives using terminal alkynes has been developed. This one-pot procedure involves C(sp)-C(sp) oxidative coupling reaction, the selective hydration and intramolecular annulation of two C≡C triple bond which is a promising synthetic strategy. Meanwhile, the benzo[b]furan and benzo[b]thiophene derivatives were facilely synthesized via Sonogashira coupling reaction, regioselective C-F bond hydration and annulation process in good yield. This reaction was a convenient and simple pathway for the synthesis of the thiophene or furan derivatives.
The development of efficient and sustainable methods for the synthesis of thiophene and furan derivatives is an important task because of the central role of this class of compounds in many natural products, pharmaceuticals and designed materials applications. In this work, a highly efficient selective synthesis of 2,5-disubstituted furan, 2,5-disubstituted thiophene derivatives, benzo[b]furan and benzo[b]thiophene derivatives using terminal alkynes has been developed. This one-pot procedure involves C(sp)-C(sp) oxidative coupling reaction, the selective hydration and intramolecular annulation of two C≡C triple bond which is a promising synthetic strategy. Meanwhile, the benzo[b]furan and benzo[b]thiophene derivatives were facilely synthesized via Sonogashira coupling reaction, regioselective C-F bond hydration and annulation process in good yield. This reaction was a convenient and simple pathway for the synthesis of the thiophene or furan derivatives.
2016, 36(10): 2437-2441
doi: 10.6023/cjoc201604004
Abstract:
In this article, a one-pot protocol was established for the synthesis of bicyclic pyrrole ketone compounds. This method based on the building blocks of heterocyclic ketene aminals 1, which reacted with oxalaldehyde 2 in 1,4-dioxane at 50℃ and triethylamine as base. As a result, a series of bicyclic pyrrole ketone compounds 3a~3i have been synthesized. This reaction has some advantages such as simple synthetic route, readily available starting materials, high yields and simple work-up procedures.
In this article, a one-pot protocol was established for the synthesis of bicyclic pyrrole ketone compounds. This method based on the building blocks of heterocyclic ketene aminals 1, which reacted with oxalaldehyde 2 in 1,4-dioxane at 50℃ and triethylamine as base. As a result, a series of bicyclic pyrrole ketone compounds 3a~3i have been synthesized. This reaction has some advantages such as simple synthetic route, readily available starting materials, high yields and simple work-up procedures.
2016, 36(10): 2442-2448
doi: 10.6023/cjoc201604013
Abstract:
A novel benzocyclobutene (BCB)-functionalized polycarbonate was synthesized. This polymer showed good solu-bility in organic solvents and could be processed by solution method. After cured at high temperature, the polymer exhibited high thermostability with 5% weight loss temperature of 451℃ and a char yield of 33% at 1000℃ in nitrogen. The cured polymer showed good hydrophobicity with water uptake of 0.21% after immersion in boiling water for 24 h. Moreover, a copolymer and poly(bisphenol A carbonate) were synthesized by bisphenol A monomer to study the influence of the existence of BCB groups on the properties of the aromatic polycarbonate. The results of comparative study showed that BCB groups can effectively improve the thermostability and hydrophoblicity of aromatic polycarbonates.
A novel benzocyclobutene (BCB)-functionalized polycarbonate was synthesized. This polymer showed good solu-bility in organic solvents and could be processed by solution method. After cured at high temperature, the polymer exhibited high thermostability with 5% weight loss temperature of 451℃ and a char yield of 33% at 1000℃ in nitrogen. The cured polymer showed good hydrophobicity with water uptake of 0.21% after immersion in boiling water for 24 h. Moreover, a copolymer and poly(bisphenol A carbonate) were synthesized by bisphenol A monomer to study the influence of the existence of BCB groups on the properties of the aromatic polycarbonate. The results of comparative study showed that BCB groups can effectively improve the thermostability and hydrophoblicity of aromatic polycarbonates.
2016, 36(10): 2449-2455
doi: 10.6023/cjoc201604027
Abstract:
A series of 2-thioalkyl-5-(4H-1,2,4-triazol-4-yl)benzo[d]oxazoles were designed and synthesized. Their anticon-vulsant activities were evaluated using maximal electroshock shock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure models in mice. The neurotoxicity was evaluated with rotarod test. The pharmacology results showed that most compounds exhibited anticonvulsant activity in MES and Sc-PTZ models. Among them, 2-(3-fluobenzyl)thio-5-(4H-1,2,4-triazol-4-yl)benzo[d]oxazole (5i) was the most potent with ED50 value of 11.4 and 31.7 mg/kg in MES and Sc-PTZ models, respectively. The TD50 value of 5i was 611.0 mg/kg, which resulted in the protective index (PI=TD50/ED50) value of 53.6 and 19.3. The pretreatment of thiosemicarbazide (an inhibitor of γ-aminobutyric acid synthesis enzyme) significantly decreased the active of 5i in MES, which suggested that the GABAergic system may contribute at least in part to the anticonvulsive action.
A series of 2-thioalkyl-5-(4H-1,2,4-triazol-4-yl)benzo[d]oxazoles were designed and synthesized. Their anticon-vulsant activities were evaluated using maximal electroshock shock (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure models in mice. The neurotoxicity was evaluated with rotarod test. The pharmacology results showed that most compounds exhibited anticonvulsant activity in MES and Sc-PTZ models. Among them, 2-(3-fluobenzyl)thio-5-(4H-1,2,4-triazol-4-yl)benzo[d]oxazole (5i) was the most potent with ED50 value of 11.4 and 31.7 mg/kg in MES and Sc-PTZ models, respectively. The TD50 value of 5i was 611.0 mg/kg, which resulted in the protective index (PI=TD50/ED50) value of 53.6 and 19.3. The pretreatment of thiosemicarbazide (an inhibitor of γ-aminobutyric acid synthesis enzyme) significantly decreased the active of 5i in MES, which suggested that the GABAergic system may contribute at least in part to the anticonvulsive action.
2016, 36(10): 2456-2462
doi: 10.6023/cjoc201602025
Abstract:
Carried out in THF-toluene at 103℃, the first one-pot Barbier-Grignard reaction to synthesize tertiary alcohols has been developed and systematically investigated using aromatic acids and unactivated aryl bromides in the presence of 10 mol% of Ta2O5. A wide range of substituted tertiary alcohols were obtained in moderate to good yields of 48%~87%. Steric and electronic effects of reactants on the reaction have been discussed. A possible mechanism catalyzed by Ta2O5 is proposed.
Carried out in THF-toluene at 103℃, the first one-pot Barbier-Grignard reaction to synthesize tertiary alcohols has been developed and systematically investigated using aromatic acids and unactivated aryl bromides in the presence of 10 mol% of Ta2O5. A wide range of substituted tertiary alcohols were obtained in moderate to good yields of 48%~87%. Steric and electronic effects of reactants on the reaction have been discussed. A possible mechanism catalyzed by Ta2O5 is proposed.
2016, 36(10): 2463-2471
doi: 10.6023/cjoc201602026
Abstract:
Natural population analysis (NPA) charge, Hirshfeld charge, electrostatic potential, average local ionization energy, orbital composition of lowest unoccupied molecular orbital (LUMO), condensed Fukui function and condensed dual descriptor were exploited to predict the reaction active sites of nucleophilic and electrophilic reactions of aromatic compounds. It was found that the predicted reaction sites of these methods were all in consistent with the experimental results. It was also found that the correlations of the prediction results of theoretical methods reflecting local hardness such as Hirshfeld charges and electrostatic potential with the experimental reaction rate were excellent no matter the reactions of aromatic compounds are nucleophilic or electrophilic. However, the prediction results of theoretical methods reflecting local softness such as the condensed Fukui function and the condensed dual descriptor were in poor correlation with the experimental reaction rates as unexpected.
Natural population analysis (NPA) charge, Hirshfeld charge, electrostatic potential, average local ionization energy, orbital composition of lowest unoccupied molecular orbital (LUMO), condensed Fukui function and condensed dual descriptor were exploited to predict the reaction active sites of nucleophilic and electrophilic reactions of aromatic compounds. It was found that the predicted reaction sites of these methods were all in consistent with the experimental results. It was also found that the correlations of the prediction results of theoretical methods reflecting local hardness such as Hirshfeld charges and electrostatic potential with the experimental reaction rate were excellent no matter the reactions of aromatic compounds are nucleophilic or electrophilic. However, the prediction results of theoretical methods reflecting local softness such as the condensed Fukui function and the condensed dual descriptor were in poor correlation with the experimental reaction rates as unexpected.
2016, 36(10): 2472-2478
doi: 10.6023/cjoc201605029
Abstract:
In order to find new cyanoacrylate lead compounds, a series of novel cyanoacrylates carrying 1,3,4-oxadiazole moiety were prepared by the method of active substructure combination. The structures of the title compounds were characterized by 1H NMR, 13C NMR and elemental analysis. Preliminary bioassay data displayed that in postemergence treatment compound 8b had 80% herbicidal activity against Stellaria media at 1500 g/ha and compound 8j showed 70% herbicidal activity against Chenopodium serotinum L. at 1500 g/ha. Additionally, compounds 8e, 8k, 8m and 8n exhibited good anti-tumor activity against HepG2 cells with the IC50values of 8.2, 5.9, 8.0 and 12.6 μmol/L, respectively.
In order to find new cyanoacrylate lead compounds, a series of novel cyanoacrylates carrying 1,3,4-oxadiazole moiety were prepared by the method of active substructure combination. The structures of the title compounds were characterized by 1H NMR, 13C NMR and elemental analysis. Preliminary bioassay data displayed that in postemergence treatment compound 8b had 80% herbicidal activity against Stellaria media at 1500 g/ha and compound 8j showed 70% herbicidal activity against Chenopodium serotinum L. at 1500 g/ha. Additionally, compounds 8e, 8k, 8m and 8n exhibited good anti-tumor activity against HepG2 cells with the IC50values of 8.2, 5.9, 8.0 and 12.6 μmol/L, respectively.
2016, 36(10): 2479-2483
doi: 10.6023/cjoc201603028
Abstract:
Oxidation of 1,1-disubstituted alkenes to ketones in the complex of CuBr and 1,2-di-tert-butyldiaziridinone in CH2Cl2 was researched. The reaction offered high yields (up to 91%) with low catalyst loading and mild conditions. The method provided a good choice for the oxidative cleavage of terminal olefins to ketones.
Oxidation of 1,1-disubstituted alkenes to ketones in the complex of CuBr and 1,2-di-tert-butyldiaziridinone in CH2Cl2 was researched. The reaction offered high yields (up to 91%) with low catalyst loading and mild conditions. The method provided a good choice for the oxidative cleavage of terminal olefins to ketones.
2016, 36(10): 2484-2488
doi: 10.6023/cjoc201604041
Abstract:
In order to find new antibacterial agent with wide spectra and high activities, 8 new (2-chloroquinolin-3-yl)meth- yleneamino guanidine derivatives were synthesized based on combination principles, whose structures were then identified by spectral methods. All of the compounds provided exhibited good inhibitory activities against the strains chosen, except Salmonella typhimurium 2421 and Pseudomonas aeruginosa 2742, of which MICs were mostly in the range of 2.0~16 μg/mL. The compound 4h showed the best broad-spectrum antibacterial activities, whose MIC value was 2.0 μg/mL against six strains. The inhibitory activities of 4h, against Staphylococcus aureus KCTC 503 and two drug-resistance bacterias (Methicillin-resistant Staphylococcus aureus CCARM 3167 and Quinolone-resistant Staphylococcus aureus CCARM 3505), were superior or equal to positive controls gatifloxacin, moxifloxacin, norfloxacin and oxacillin.
In order to find new antibacterial agent with wide spectra and high activities, 8 new (2-chloroquinolin-3-yl)meth- yleneamino guanidine derivatives were synthesized based on combination principles, whose structures were then identified by spectral methods. All of the compounds provided exhibited good inhibitory activities against the strains chosen, except Salmonella typhimurium 2421 and Pseudomonas aeruginosa 2742, of which MICs were mostly in the range of 2.0~16 μg/mL. The compound 4h showed the best broad-spectrum antibacterial activities, whose MIC value was 2.0 μg/mL against six strains. The inhibitory activities of 4h, against Staphylococcus aureus KCTC 503 and two drug-resistance bacterias (Methicillin-resistant Staphylococcus aureus CCARM 3167 and Quinolone-resistant Staphylococcus aureus CCARM 3505), were superior or equal to positive controls gatifloxacin, moxifloxacin, norfloxacin and oxacillin.
2016, 36(10): 2489-2495
doi: 10.6023/cjoc201604042
Abstract:
Novel pinanyl thiazole derivatives were synthesized from nopinone which was a derivative from β-pinene by con-densation and cyclization, and their bioactivities were also examined in this paper. Nopinone obtained from oxidation of β-pinene was condensed with thiosemicarbazide into nopinone thiosemicarbazone, and thiazole derivatives 2a~2l were prepared via cyclization of nopinone thiosemicarbazone with α-haloketones. The structures of compounds 2a~2l were characterized with 1H NMR, 13C NMR, IR and HRMS, and the antibacterial activity, anti-inflammatory activity on human umbilical vein endothelial cells (HUVECs), and insecticidal activity on crape myrtle aphids of compounds 2a~2l were also examined. Test results showed that compound 2b was a more potent bactericide and fungicide than others because of its good activities against bacteria and fungi, compound 2a had strong anti-inflammatory activity towards HUVECs and had the similar effect to that of aspirin, and compounds 2e, 2h, 2i and 2k had a certain insecticidal activities against crape myrtle aphids.
Novel pinanyl thiazole derivatives were synthesized from nopinone which was a derivative from β-pinene by con-densation and cyclization, and their bioactivities were also examined in this paper. Nopinone obtained from oxidation of β-pinene was condensed with thiosemicarbazide into nopinone thiosemicarbazone, and thiazole derivatives 2a~2l were prepared via cyclization of nopinone thiosemicarbazone with α-haloketones. The structures of compounds 2a~2l were characterized with 1H NMR, 13C NMR, IR and HRMS, and the antibacterial activity, anti-inflammatory activity on human umbilical vein endothelial cells (HUVECs), and insecticidal activity on crape myrtle aphids of compounds 2a~2l were also examined. Test results showed that compound 2b was a more potent bactericide and fungicide than others because of its good activities against bacteria and fungi, compound 2a had strong anti-inflammatory activity towards HUVECs and had the similar effect to that of aspirin, and compounds 2e, 2h, 2i and 2k had a certain insecticidal activities against crape myrtle aphids.
2016, 36(10): 2496-2498
doi: 10.6023/cjoc201604012
Abstract:
By silica gel, MCI column chromatographic and preparative HPLC (high performance liquid chromatography) technologies, six nitrogen compounds were isolated from the whole parts of Gymnotheca involucrata. By using spectroscopic techniques including NMR and MS, these compounds were identified as 2-(1-hydroxy-6-methoxy-4-oxocyclohexa-2-ene- 1-yl)acetonitrile (1), 10-methoxy-1-oxa-3-azaspiro[4.5]dec-2,6-diene-8-one (2), 2-(1-hydroxy-4-oxocyclohexa-2,5-dien-1-yl)- acetonitrile (3), 1-oxa-3-azaspiro[4.5]dec-2-ene-8-one (4), 1-oxa-3-azaspiro[4.5]dec-2,6-diene-8-one (5) and 4-hydroxybenzyl acetonitrile (6). Compounds 1 and 2 are new compounds, compound 3 is a new natural product, and compounds 4~6 were isolated from this plant for the first time.
By silica gel, MCI column chromatographic and preparative HPLC (high performance liquid chromatography) technologies, six nitrogen compounds were isolated from the whole parts of Gymnotheca involucrata. By using spectroscopic techniques including NMR and MS, these compounds were identified as 2-(1-hydroxy-6-methoxy-4-oxocyclohexa-2-ene- 1-yl)acetonitrile (1), 10-methoxy-1-oxa-3-azaspiro[4.5]dec-2,6-diene-8-one (2), 2-(1-hydroxy-4-oxocyclohexa-2,5-dien-1-yl)- acetonitrile (3), 1-oxa-3-azaspiro[4.5]dec-2-ene-8-one (4), 1-oxa-3-azaspiro[4.5]dec-2,6-diene-8-one (5) and 4-hydroxybenzyl acetonitrile (6). Compounds 1 and 2 are new compounds, compound 3 is a new natural product, and compounds 4~6 were isolated from this plant for the first time.
2016, 36(10): 2499-2503
doi: 10.6023/cjoc201604021
Abstract:
Chroman skeleton exists in many natural and synthetic biologically active materials. A highly efficient method for the synthesis of chromans via reaction of phenols with prenyl bromide catalyzed by zinc chloride is described, which provides a practical process to afford this type of biologically important compounds in good yields using commercially available and inexpensive catalyst under mild conditions.
Chroman skeleton exists in many natural and synthetic biologically active materials. A highly efficient method for the synthesis of chromans via reaction of phenols with prenyl bromide catalyzed by zinc chloride is described, which provides a practical process to afford this type of biologically important compounds in good yields using commercially available and inexpensive catalyst under mild conditions.
2016, 36(10): 2504-2509
doi: 10.6023/cjoc201604031
Abstract:
The isoquinoline and dihydroisoquinoline ring systems are found as the core nucleus in a wide variety of natural products and pharmaceutical agents with good biologically activity. Isoquinoline, benzoxazine-fused isoquinlines and pyrazo-lo[5,1-a]isoquinolines are prepared from o-alkynyl aldehydes and nitrogen-containing compounds via tandem reactions catalyzed by CuI or AgNO3. The reactions have some advantages, such as mild reaction conditions, simple operation and easily available catalysts.
The isoquinoline and dihydroisoquinoline ring systems are found as the core nucleus in a wide variety of natural products and pharmaceutical agents with good biologically activity. Isoquinoline, benzoxazine-fused isoquinlines and pyrazo-lo[5,1-a]isoquinolines are prepared from o-alkynyl aldehydes and nitrogen-containing compounds via tandem reactions catalyzed by CuI or AgNO3. The reactions have some advantages, such as mild reaction conditions, simple operation and easily available catalysts.
