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2017 Volume 37 Issue 10
2017, 37(10): 2457-2480
doi: 10.6023/cjoc201704015
Abstract:
In thermally activated delayed fluorescence (TADF) based emitters, the excitons from the lowest triplet state (T1) can be efficiently upconverted into the lowest singlet (S1) state via reverse intersystem crossing (RISC) process due to the small energy gap (ΔEST) between their S1 and T1 states, harvesting both S1 and T1 excitons for emission, with non-noble metals, which can break the internal/external quantum efficiency (IQE/EQE) (≤25%/≤ 5%) limitation of conventional fluorescence based organic light-emitting diodes (OLEDs). Their no-noble metals feature makes them more competitive than phosphorescence materials in making OLEDs. Among the vast of TADF materials, eletrons donor-acceptor (D-A) type is one of the most popular TADF material due to their outstanding performance and convenience of preparation. On the other hand, efficient blue emitters are facing issues related to their stability and color purity that makes their development quite challenging for researchers. In this review, the D-A type blue TADF emitters and OLEDs reported recently are summarized, the mechanism of TADF based OLEDs and the principle of designs are elaborated, and a full vision of its development is made.
In thermally activated delayed fluorescence (TADF) based emitters, the excitons from the lowest triplet state (T1) can be efficiently upconverted into the lowest singlet (S1) state via reverse intersystem crossing (RISC) process due to the small energy gap (ΔEST) between their S1 and T1 states, harvesting both S1 and T1 excitons for emission, with non-noble metals, which can break the internal/external quantum efficiency (IQE/EQE) (≤25%/≤ 5%) limitation of conventional fluorescence based organic light-emitting diodes (OLEDs). Their no-noble metals feature makes them more competitive than phosphorescence materials in making OLEDs. Among the vast of TADF materials, eletrons donor-acceptor (D-A) type is one of the most popular TADF material due to their outstanding performance and convenience of preparation. On the other hand, efficient blue emitters are facing issues related to their stability and color purity that makes their development quite challenging for researchers. In this review, the D-A type blue TADF emitters and OLEDs reported recently are summarized, the mechanism of TADF based OLEDs and the principle of designs are elaborated, and a full vision of its development is made.
2017, 37(10): 2481-2497
doi: 10.6023/cjoc201705034
Abstract:
Organoboron compounds are wildly used in organic synthesis, materials science, life and health science, etc. The development of synthetic methodologies of organoborons has therefore gained intense attention nowadays. Typically, Bis(pinacolato)diboron (B2Pin2), pinacolborane (HBpin) and catecholatoborane (HBCat) are predominantly used as boron reagents in catalytic C-B bond forming reactions. Different from the above traditional boron reagents, borane adducts with strong Lewis bases, such as amines, phosphines, and N-heterocyclic carbenes, are promising boron reagents because of their readily accessibility, relatively high stability, and easy operation. Moreover, the different chemical properties of these stable borane adducts towards the traditional boron reagents provide possibilities for development of new C-B bond formation reactions. The applications of the stable borane adducts as terminal boron reagents in hydroboration of alkenes or alkynes, C-H bond borylation, carbene insertion into B-H bonds, cascade cyclization initiated by boryl radicals and substitutions, which provide new methods for the preparation of organoborons are reviewed in this paper.
Organoboron compounds are wildly used in organic synthesis, materials science, life and health science, etc. The development of synthetic methodologies of organoborons has therefore gained intense attention nowadays. Typically, Bis(pinacolato)diboron (B2Pin2), pinacolborane (HBpin) and catecholatoborane (HBCat) are predominantly used as boron reagents in catalytic C-B bond forming reactions. Different from the above traditional boron reagents, borane adducts with strong Lewis bases, such as amines, phosphines, and N-heterocyclic carbenes, are promising boron reagents because of their readily accessibility, relatively high stability, and easy operation. Moreover, the different chemical properties of these stable borane adducts towards the traditional boron reagents provide possibilities for development of new C-B bond formation reactions. The applications of the stable borane adducts as terminal boron reagents in hydroboration of alkenes or alkynes, C-H bond borylation, carbene insertion into B-H bonds, cascade cyclization initiated by boryl radicals and substitutions, which provide new methods for the preparation of organoborons are reviewed in this paper.
2017, 37(10): 2498-2511
doi: 10.6023/cjoc201705003
Abstract:
As cheap, environmentally friendly, easily handled strong oxidants, persulfates have been widely used in organic synthesis. It is well known that persulfates may decompose to sulfate radical anions (SO4-·) under heating, light irradiation or transition-metal reductive conditions. Studies indicate that the sulfate radical anion is a powerful single-electron oxidant, which can oxidize a variety of neutral molecules and anions to give the corresponding radicals. The new generated radicals can further undergo a series of chemical transformations to provide structurally diverse and useful compounds. Recent radical reactions promoted by persulfates are summarized. The full text contains five parts. In the first and second parts, recent advance in the radical cyclization reactions and functionalization of C-H bonds promoted by persulfates is discussed. The third part introduced the persulfates-mediated photocatalytic reactions. The fourth part emphasized persulfates-promoted other free radical reactions. Finally, some perspectives on the future development of this chemistry are given.
As cheap, environmentally friendly, easily handled strong oxidants, persulfates have been widely used in organic synthesis. It is well known that persulfates may decompose to sulfate radical anions (SO4-·) under heating, light irradiation or transition-metal reductive conditions. Studies indicate that the sulfate radical anion is a powerful single-electron oxidant, which can oxidize a variety of neutral molecules and anions to give the corresponding radicals. The new generated radicals can further undergo a series of chemical transformations to provide structurally diverse and useful compounds. Recent radical reactions promoted by persulfates are summarized. The full text contains five parts. In the first and second parts, recent advance in the radical cyclization reactions and functionalization of C-H bonds promoted by persulfates is discussed. The third part introduced the persulfates-mediated photocatalytic reactions. The fourth part emphasized persulfates-promoted other free radical reactions. Finally, some perspectives on the future development of this chemistry are given.
2017, 37(10): 2512-2525
doi: 10.6023/cjoc201604029
Abstract:
In this paper, the recent research progress in transition-metal catalyzed bicyclic olefin addition reactions is reviewed, mainly including Ru, Rh, Ir, Pd, Cu, Co, Ni and Fe etc. Moreover, the possible mechanisms of some parts of addition reactions are also discussed.
In this paper, the recent research progress in transition-metal catalyzed bicyclic olefin addition reactions is reviewed, mainly including Ru, Rh, Ir, Pd, Cu, Co, Ni and Fe etc. Moreover, the possible mechanisms of some parts of addition reactions are also discussed.
2017, 37(10): 2526-2543
doi: 10.6023/cjoc201703017
Abstract:
(+)-Neopeltolide was isolated from a deep-water sponge of the family neopeltidae. Due to its attractive novel structure and highly potent anticancer activity, more than twenty total and formal syntheses have been reported in last decade. Herein, the synthetic studies toward the total and formal syntheses of neopeltolide are reviewed according to the synthetic strategies toward the macrolactone core.
(+)-Neopeltolide was isolated from a deep-water sponge of the family neopeltidae. Due to its attractive novel structure and highly potent anticancer activity, more than twenty total and formal syntheses have been reported in last decade. Herein, the synthetic studies toward the total and formal syntheses of neopeltolide are reviewed according to the synthetic strategies toward the macrolactone core.
2017, 37(10): 2544-2554
doi: 10.6023/cjoc201704051
Abstract:
A dual-catalysis system merging the visible light photoredox with transition metal nickel catalysis enables a new strategy to build the novel carbon-carbon and carbon-heteroatom bond, which are not generally possible via using either photoredox or nickel catalysis alone. This mild, green and promising protocol has attracted the interest of some scientific researchers. In this review, the recent progress of nickel/photoredox dual catalysis is summarized.
A dual-catalysis system merging the visible light photoredox with transition metal nickel catalysis enables a new strategy to build the novel carbon-carbon and carbon-heteroatom bond, which are not generally possible via using either photoredox or nickel catalysis alone. This mild, green and promising protocol has attracted the interest of some scientific researchers. In this review, the recent progress of nickel/photoredox dual catalysis is summarized.
2017, 37(10): 2555-2568
doi: 10.6023/cjoc201704011
Abstract:
Asymmetric hydrosilylation of alkenes, which has been recognized as an important method for the preparations of optically active secondary alcohols, deserves widespread attention over the world. It is reported that such reaction can be catalyzed by Pd-monodentate phosphorus catalysts with excellent reactivity and enantioselectivity. In the past decades, a wide variety of chiral monodentate phosphorus ligands have been developed because of their stable structure, facile synthesis, convenient modification, unique efficiency. Among them, there are three predominant classes of ligands-phosphines based on an axially chiral biaryl scaffold, phosphines based on a planar chiral ferrocene scaffold and chiral phosphoramidites. Herein, the recent advances in asymmetric hydrosilylation of alkyl-substituted alkenes, styrene derivatives, 1, 3-dienes and other carbon-carbon double bond compounds catalyzed by palladium monodentate phosphorus catalysts are summarized. The perspective is also discussed.
Asymmetric hydrosilylation of alkenes, which has been recognized as an important method for the preparations of optically active secondary alcohols, deserves widespread attention over the world. It is reported that such reaction can be catalyzed by Pd-monodentate phosphorus catalysts with excellent reactivity and enantioselectivity. In the past decades, a wide variety of chiral monodentate phosphorus ligands have been developed because of their stable structure, facile synthesis, convenient modification, unique efficiency. Among them, there are three predominant classes of ligands-phosphines based on an axially chiral biaryl scaffold, phosphines based on a planar chiral ferrocene scaffold and chiral phosphoramidites. Herein, the recent advances in asymmetric hydrosilylation of alkyl-substituted alkenes, styrene derivatives, 1, 3-dienes and other carbon-carbon double bond compounds catalyzed by palladium monodentate phosphorus catalysts are summarized. The perspective is also discussed.
2017, 37(10): 2569-2589
doi: 10.6023/cjoc201702033
Abstract:
The recent progress in ring-opening reactions of aziridines by various carbon nucleophiles, such as alkynes, nitriles, arenes, heteroarenes, active methylene compounds, organometallic reagents and so on, is reviewed. Moreover, the prospects of future development are also discussed.
The recent progress in ring-opening reactions of aziridines by various carbon nucleophiles, such as alkynes, nitriles, arenes, heteroarenes, active methylene compounds, organometallic reagents and so on, is reviewed. Moreover, the prospects of future development are also discussed.
2017, 37(10): 2590-2608
doi: 10.6023/cjoc201702041
Abstract:
Since the first stable N-heterocyclic carbene was isolated by Arduengo in 1991, N-heterocyclic carbine has developed rapidly as a kind of efficient organic catalyst. It plays important role in building complex molecules in organic synthesis for the characteristics of umpolung. Some special Lewis bases and oxidants can induce carbine reaction with carbonyl to form Breslow intermediates, enol and homoenolate, which expand the reaction greatly. In this paper, the recent progresses in organic catalytic reactions including Stetter reaction, a3-d3 umpolung catalyzed by carbines are reviewed.
Since the first stable N-heterocyclic carbene was isolated by Arduengo in 1991, N-heterocyclic carbine has developed rapidly as a kind of efficient organic catalyst. It plays important role in building complex molecules in organic synthesis for the characteristics of umpolung. Some special Lewis bases and oxidants can induce carbine reaction with carbonyl to form Breslow intermediates, enol and homoenolate, which expand the reaction greatly. In this paper, the recent progresses in organic catalytic reactions including Stetter reaction, a3-d3 umpolung catalyzed by carbines are reviewed.
2017, 37(10): 2609-2618
doi: 10.6023/cjoc201704024
Abstract:
Polyconjugated nitrodienynes/nitroenynes as nitroolefin derivatives are good kind of electrophiles and have been widely used in organic synthesis. There are multiple reaction sites due to the conjugated system. Therefore, competitive reactions of regioselectivity in the reaction process are existence, such as 1, 4-addition reaction, 1, 6-addition reaction, and even 1, 8-addition reaction. The recent progress of the synthesis of nitrodienynes/nitroenynes and their applications in organic synthesis are summarized.
Polyconjugated nitrodienynes/nitroenynes as nitroolefin derivatives are good kind of electrophiles and have been widely used in organic synthesis. There are multiple reaction sites due to the conjugated system. Therefore, competitive reactions of regioselectivity in the reaction process are existence, such as 1, 4-addition reaction, 1, 6-addition reaction, and even 1, 8-addition reaction. The recent progress of the synthesis of nitrodienynes/nitroenynes and their applications in organic synthesis are summarized.
2017, 37(10): 2619-2639
doi: 10.6023/cjoc201703023
Abstract:
A wide variety of phenazine compounds are no stranger to organic chemistry researchers, it widely exists in organic natural products together with good biological activity. The synthetic process is simple and the functionalization of molecular structure is comparatively easy of phenazine compounds with natural skeleton. These compounds with multiple sites and large conjugated system, which make it easy to form hydrogen bond, ionic bond and π-π interaction and so on. Therefore, the phenazine compounds have extensive application in supramolecular chemistry. Molecular recognition (MR) and supramolecular self-assembly (MS-A) are two important research direction of supramolecular chemistry. The advances in the research of the development on application of phenazine derivatives in MR and MS-A in recent years are highlighted. According to different type of guest, the MR is grouped into three categories, including anion recognition (AR), cationic recognition (CR) and neutral molecular recognition (NMR). According to the difference of induction factors between guest and phenazine derivatives, the MS-A is grouped into four categories, including self-assembly induced by hydrogen bonding (HBSA), self-assembly induced by accumulation (ASA), self-assembly induced by metal-ligand (M-LSA), self-assembly induced by cooperation of multiple factors (MFSA), and self-assembly induced by the outside environment (OESA).
A wide variety of phenazine compounds are no stranger to organic chemistry researchers, it widely exists in organic natural products together with good biological activity. The synthetic process is simple and the functionalization of molecular structure is comparatively easy of phenazine compounds with natural skeleton. These compounds with multiple sites and large conjugated system, which make it easy to form hydrogen bond, ionic bond and π-π interaction and so on. Therefore, the phenazine compounds have extensive application in supramolecular chemistry. Molecular recognition (MR) and supramolecular self-assembly (MS-A) are two important research direction of supramolecular chemistry. The advances in the research of the development on application of phenazine derivatives in MR and MS-A in recent years are highlighted. According to different type of guest, the MR is grouped into three categories, including anion recognition (AR), cationic recognition (CR) and neutral molecular recognition (NMR). According to the difference of induction factors between guest and phenazine derivatives, the MS-A is grouped into four categories, including self-assembly induced by hydrogen bonding (HBSA), self-assembly induced by accumulation (ASA), self-assembly induced by metal-ligand (M-LSA), self-assembly induced by cooperation of multiple factors (MFSA), and self-assembly induced by the outside environment (OESA).
2017, 37(10): 2640-2646
doi: 10.6023/cjoc201704010
Abstract:
Three novel carbazole-thiosemicarbazides based Schiff-base were synthesized. The recognition ability of representive 2-((N-heptane-carbazol-3-yl)methylidene)hydrazine carbothioamide (L2) to metal ions was investigated by naked-eye, UV-Vis, fluorescence and mass spectra. The experimental results showed that this compound had a good water solubility and can be investigated in DMSO-H2O (V:V=6:4, Tris-HCl buffer, pH=7.0). The compound L2 in the DMSO-H2O displayed a dis-tinct color change from colorless to yellow upon the addition of Cu2+, other metal ions did not induce significant colour changes, which indicated that Schiff base L2 can be used as a probe with naked eye detection for Cu2+. The fluorescence spectra showed that the probe L2 was a high selective and sensitive "turn-off" fluorescence probe for Cu2+ in DMSO-H2O (V:V=6:4, Tris-HCl buffer, pH=7.0). The association constant between the probe L2 and Cu2+ was detected to be 3.42×104 L·mol-1, and the detection limit was calculated to be 8.96×10-6 mol·L-1. MS analysis showed a 1:1 binding stoichiometry between Cu2+ and L2. The detection limit of L2 for Cu2+ was far lower than the maximum allowable level of World Health Organization (WHO) limit (20 μmol·L-1) for drinking water.
Three novel carbazole-thiosemicarbazides based Schiff-base were synthesized. The recognition ability of representive 2-((N-heptane-carbazol-3-yl)methylidene)hydrazine carbothioamide (L2) to metal ions was investigated by naked-eye, UV-Vis, fluorescence and mass spectra. The experimental results showed that this compound had a good water solubility and can be investigated in DMSO-H2O (V:V=6:4, Tris-HCl buffer, pH=7.0). The compound L2 in the DMSO-H2O displayed a dis-tinct color change from colorless to yellow upon the addition of Cu2+, other metal ions did not induce significant colour changes, which indicated that Schiff base L2 can be used as a probe with naked eye detection for Cu2+. The fluorescence spectra showed that the probe L2 was a high selective and sensitive "turn-off" fluorescence probe for Cu2+ in DMSO-H2O (V:V=6:4, Tris-HCl buffer, pH=7.0). The association constant between the probe L2 and Cu2+ was detected to be 3.42×104 L·mol-1, and the detection limit was calculated to be 8.96×10-6 mol·L-1. MS analysis showed a 1:1 binding stoichiometry between Cu2+ and L2. The detection limit of L2 for Cu2+ was far lower than the maximum allowable level of World Health Organization (WHO) limit (20 μmol·L-1) for drinking water.
2017, 37(10): 2647-2654
doi: 10.6023/cjoc201704035
Abstract:
Pyrimidine-contained novel rod-coil shaped N^C^N-type tridentate ligand 1 and its platinum(Ⅱ) complexe 1-Pt were synthesized, and their structures were characterized by NMR spectroscopy and MALDI-TOF mass spectrometry. The self-assembly and optical properties of 1-Pt were investigated with FE-SEM, UV-Vis and fluorescence spectroscopies. The result indicated that the unique rod-coil structure of 1-Pt enhanced intermolecular π-π stacking and showed excellent self-assembly performance in organic solvents which allowing for modulation of luminescence.
Pyrimidine-contained novel rod-coil shaped N^C^N-type tridentate ligand 1 and its platinum(Ⅱ) complexe 1-Pt were synthesized, and their structures were characterized by NMR spectroscopy and MALDI-TOF mass spectrometry. The self-assembly and optical properties of 1-Pt were investigated with FE-SEM, UV-Vis and fluorescence spectroscopies. The result indicated that the unique rod-coil structure of 1-Pt enhanced intermolecular π-π stacking and showed excellent self-assembly performance in organic solvents which allowing for modulation of luminescence.
2017, 37(10): 2663-2668
doi: 10.6023/cjoc201704007
Abstract:
A new method for practical synthesis of 1, 1'-biisoquinolines is described. Treatment of N, N'-diphenethyloxal-amides (1a~1j) with phosphoryl trichloride in acetonitrile or toluene under N2 at reflux produced 3, 3', 4, 4'-tetrahydro-1, 1'-biisoquinolines (2a~2j) via Bischler-Napieralski cyclization. Subsequently, compounds 2a~2j underwent Cu(OAc)2-catalyzed aerobic oxidative aromatization in dimethyl sulfoxide (DMSO) in the presence of a catalytic amount of 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU) to afford a series of 1, 1'-biisoquinolines (3a~3j) in 70%~88% overall yields (2 steps).
A new method for practical synthesis of 1, 1'-biisoquinolines is described. Treatment of N, N'-diphenethyloxal-amides (1a~1j) with phosphoryl trichloride in acetonitrile or toluene under N2 at reflux produced 3, 3', 4, 4'-tetrahydro-1, 1'-biisoquinolines (2a~2j) via Bischler-Napieralski cyclization. Subsequently, compounds 2a~2j underwent Cu(OAc)2-catalyzed aerobic oxidative aromatization in dimethyl sulfoxide (DMSO) in the presence of a catalytic amount of 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU) to afford a series of 1, 1'-biisoquinolines (3a~3j) in 70%~88% overall yields (2 steps).
2017, 37(10): 2669-2677
doi: 10.6023/cjoc201704040
Abstract:
An efficient Pd(Ⅱ)-catalyzed synthesis of benzyl benzoates via direct functionalization of benzyl C(sp3)-H bonds was developed. The method features a broad substrate scope. This method features high tolerance of functional groups, mild reaction condition, and high chemoselective when there are multiple active C(sp3)-H bonds. A plausible oxidative coupling mechanism was proposed on the basis of mechanistic studies.
An efficient Pd(Ⅱ)-catalyzed synthesis of benzyl benzoates via direct functionalization of benzyl C(sp3)-H bonds was developed. The method features a broad substrate scope. This method features high tolerance of functional groups, mild reaction condition, and high chemoselective when there are multiple active C(sp3)-H bonds. A plausible oxidative coupling mechanism was proposed on the basis of mechanistic studies.
2017, 37(10): 2685-2689
doi: 10.6023/cjoc201703001
Abstract:
Starting from the readily available maleic anhydride and (R)-1, 1'-bi-2-naphthol (BINOL), an efficient method for the synthesis of a new class of chiral maleimide derivatives with C2-symmetry was described, involving Williamson ether synthesis, Suzuki coupling reaction and deprotection reaction by microwave to give 3, 4-[(R)-3, 3'-diaryl-1, 1'-binaphthyl-2, 2'-dioxy]-maleimides in 6.2%~16% yields. Moreover, the structures of the target compound and key intermediates were confirmed by 1H NMR, 13C NMR, HRMS and IR techniques.
Starting from the readily available maleic anhydride and (R)-1, 1'-bi-2-naphthol (BINOL), an efficient method for the synthesis of a new class of chiral maleimide derivatives with C2-symmetry was described, involving Williamson ether synthesis, Suzuki coupling reaction and deprotection reaction by microwave to give 3, 4-[(R)-3, 3'-diaryl-1, 1'-binaphthyl-2, 2'-dioxy]-maleimides in 6.2%~16% yields. Moreover, the structures of the target compound and key intermediates were confirmed by 1H NMR, 13C NMR, HRMS and IR techniques.
2017, 37(10): 2690-2696
doi: 10.6023/cjoc201705004
Abstract:
The method was constructed for synthesis of pyrrolone compounds, which was based on the reaction of 1, 1-endiamine (1) with maleic anhydride (2) in 1, 4-dioxane at reflux in alkali condition (Et3N). As a result, a series of iminopyrrolone compounds have been synthesized by this reaction. This protocol possesses some advantages including readily available starting materials, simple operation and concise synthetic route and so on.
The method was constructed for synthesis of pyrrolone compounds, which was based on the reaction of 1, 1-endiamine (1) with maleic anhydride (2) in 1, 4-dioxane at reflux in alkali condition (Et3N). As a result, a series of iminopyrrolone compounds have been synthesized by this reaction. This protocol possesses some advantages including readily available starting materials, simple operation and concise synthetic route and so on.
2017, 37(10): 2697-2704
doi: 10.6023/cjoc201704027
Abstract:
The cyanuric chloride and benzene Friedel-Crafts arylation using Lewis acid catalyst in high pressure autoclave was studied in this manuscript. The aim compounds 2, 4-dichloro-6-phenyl-1, 3, 5-triazine and 2, 4, 6-triphenyl-1, 3, 5-triazine could be got with high selectivity and yields by varying reaction temperature, substrate and catalyst amount, which application was expecting and promising. The transition state was obtained by quantum calculation density functional theory (DFT) method using Gaussian software, and the experimental results and mechanism of this reaction were discussed from the point of dynamics and thermo-dynamics.
The cyanuric chloride and benzene Friedel-Crafts arylation using Lewis acid catalyst in high pressure autoclave was studied in this manuscript. The aim compounds 2, 4-dichloro-6-phenyl-1, 3, 5-triazine and 2, 4, 6-triphenyl-1, 3, 5-triazine could be got with high selectivity and yields by varying reaction temperature, substrate and catalyst amount, which application was expecting and promising. The transition state was obtained by quantum calculation density functional theory (DFT) method using Gaussian software, and the experimental results and mechanism of this reaction were discussed from the point of dynamics and thermo-dynamics.
2017, 37(10): 2705-2710
doi: 10.6023/cjoc201704032
Abstract:
A series of novel acyl thiourea derivatives containing pyrazole moiety were designed and synthesized from ethyl acetoacetate, triethyl orthoformate, methylhydrazine by multi-step reactions. Their structures were characterized by 1H NMR, 13C NMR and HRMS. The target compounds were evaluated for their fungicidal activity. The results indicated that some of the title compounds displayed certain fungicidal activities against Botryospuaeria berengeriana. The docking results indicated that the hydrogen bond and π(σ)-π interaction formed between N-((2, 6-diethylphenyl)carbamothioyl)-1, 3-dimethyl-1H-pyrazole-4-carboxamide (6k) and succinodehydrogenase.
A series of novel acyl thiourea derivatives containing pyrazole moiety were designed and synthesized from ethyl acetoacetate, triethyl orthoformate, methylhydrazine by multi-step reactions. Their structures were characterized by 1H NMR, 13C NMR and HRMS. The target compounds were evaluated for their fungicidal activity. The results indicated that some of the title compounds displayed certain fungicidal activities against Botryospuaeria berengeriana. The docking results indicated that the hydrogen bond and π(σ)-π interaction formed between N-((2, 6-diethylphenyl)carbamothioyl)-1, 3-dimethyl-1H-pyrazole-4-carboxamide (6k) and succinodehydrogenase.
2017, 37(10): 2711-2716
doi: 10.6023/cjoc201705021
Abstract:
A novel and catalyst-free one-pot method for the preparation of quinazoline compounds has been reported. Of the prepared 15 quinazoline compounds, three are new compounds. Their yields are among 37%~95%. The effects of electron effect and steric hindrance on the reaction were discussed. A plausible novel mechanism concerning repeating nucleophilic addition and elimination to give quinazoline has been proposed. By this mechanism, the reaction could be applied to acid anhydride instead of N, N-dimethylformamide (DMF).
A novel and catalyst-free one-pot method for the preparation of quinazoline compounds has been reported. Of the prepared 15 quinazoline compounds, three are new compounds. Their yields are among 37%~95%. The effects of electron effect and steric hindrance on the reaction were discussed. A plausible novel mechanism concerning repeating nucleophilic addition and elimination to give quinazoline has been proposed. By this mechanism, the reaction could be applied to acid anhydride instead of N, N-dimethylformamide (DMF).
2017, 37(10): 2717-2724
doi: 10.6023/cjoc201704039
Abstract:
To find new lead compounds with muti-bioactivities, a series of novel triketone derivatives containing 4-substituted cyclopentane-1, 3-dione were designed on the base of various commercial products. The target compounds were synthesized from cyclopentane-1, 3-dione in six steps. Their structures were confirmed by IR, 1H NMR spectra and HRMS. The preliminary greenhouse bioassay results indicated that some compounds showed obvious inhibition effects against Brassica campestris, and the inhibition rate was more than 80% at 100 μg/mL. In the pre-and post-emergence, some of them exhibited excellent herbicidal activities against Brassica campestris, and the herbicidal activity was more than 90% at 1500 g/ha.
To find new lead compounds with muti-bioactivities, a series of novel triketone derivatives containing 4-substituted cyclopentane-1, 3-dione were designed on the base of various commercial products. The target compounds were synthesized from cyclopentane-1, 3-dione in six steps. Their structures were confirmed by IR, 1H NMR spectra and HRMS. The preliminary greenhouse bioassay results indicated that some compounds showed obvious inhibition effects against Brassica campestris, and the inhibition rate was more than 80% at 100 μg/mL. In the pre-and post-emergence, some of them exhibited excellent herbicidal activities against Brassica campestris, and the herbicidal activity was more than 90% at 1500 g/ha.
2017, 37(10): 2725-2735
doi: 10.6023/cjoc201705013
Abstract:
With the aim of obtaining potential antitumor candidates with more efficiency and more economic value. 40 2, 4, 6-trisubstituted pyrimidine derivatives bearing chalcone moiety were synthesized via cyclization, chlorination, substitution with benzoylacetate and ethylacetoacetate as the starting materials. The structures of target products were confirmed by 1H NMR, I3C NMR and HRMS. 2, 4, 6-Trisubstituted pyrimidine derivatives bearing chalcone moiety were evaluated for anticancer activity on four human cancer cell lines including EC-109, MGC-803, HepG-2 and MDA-MB-231 by CCK-8 (cell counting Kit-8) assay. Among them, (E)-1-(4-((2-(((1H-benzo[d]imidazol-2-yl)methyl)thio)-6-methylpyrimidin-4-yl)amino)-phe-nyl)-3-(3, 4, 5-trimethoxyphenyl)prop-2-en-1-one (13u) were more cytotoxic against MGC-803 and MDA-MB-231 cell lines, with IC50 values of 0.99 and 1.77 μmol·L-1, respectively.
With the aim of obtaining potential antitumor candidates with more efficiency and more economic value. 40 2, 4, 6-trisubstituted pyrimidine derivatives bearing chalcone moiety were synthesized via cyclization, chlorination, substitution with benzoylacetate and ethylacetoacetate as the starting materials. The structures of target products were confirmed by 1H NMR, I3C NMR and HRMS. 2, 4, 6-Trisubstituted pyrimidine derivatives bearing chalcone moiety were evaluated for anticancer activity on four human cancer cell lines including EC-109, MGC-803, HepG-2 and MDA-MB-231 by CCK-8 (cell counting Kit-8) assay. Among them, (E)-1-(4-((2-(((1H-benzo[d]imidazol-2-yl)methyl)thio)-6-methylpyrimidin-4-yl)amino)-phe-nyl)-3-(3, 4, 5-trimethoxyphenyl)prop-2-en-1-one (13u) were more cytotoxic against MGC-803 and MDA-MB-231 cell lines, with IC50 values of 0.99 and 1.77 μmol·L-1, respectively.
2017, 37(10): 2736-2744
doi: 10.6023/cjoc201701014
Abstract:
Using 3, 3'-diamino-4, 4'-azoxyfurazan (DAOAF) and 2, 2-dimethyl-5-nitro-5-nitroso-1, 3-dioxane (DMNNDO) as starting materials, energetic compound 3, 3'-bis(fluoronitromethyl-ONN-azoxy)azoxyfurazan (FDNAF) was designed and synthesized via oxidation coupling, hydrolysis, bromization, reduction, nitration, salification and fluorination etc., and the structures of all the intermediates and the title compound were characterized by IR, 1H NMR, 13C NMR, 15N NMR、19F NMR and elemental analysis. Using HCl/CH3CH2OH as the hydrolysis system instead of AcCl/CH3OH, the condition of hydrolysis reaction was optimized, the reaction time was shortened from 18 h to 2 h and the purity of raw product was improved to 93%. The bromination reaction conditions were also studied. Under the optimum conditions with the temperature of 20℃ and the reaction time of 30 min, the brominated product was obtained with a yield of 51.5%. Based on B3LYP method of density function theory, 13C NMR, 15N NMR and IR chemical shifts were studied theoretically, which agreed with experimental data. The physicochemical properties, detonation performances and thermal behaviors of 3, 3'-bis(nitromethyl-ONN-azoxy)azoxyfurazan (BNMAF), 3, 3'-bis(dinitromethyl-ONN-azoxy)azoxyfurazan (BDNAF) and FDNAF were studied and analyzed. The results proved that FDNAF is a potential energetic compound with the theoretical density of 2.02 g·cm-3, the decomposition point of 233.4℃, the oxygen balance of 6.72%, the explosion velocity of 9735 m·s-1, the detonation pressure of 44.9 GPa, and the characteristic drop height of impact sensitivity of 36 cm.
Using 3, 3'-diamino-4, 4'-azoxyfurazan (DAOAF) and 2, 2-dimethyl-5-nitro-5-nitroso-1, 3-dioxane (DMNNDO) as starting materials, energetic compound 3, 3'-bis(fluoronitromethyl-ONN-azoxy)azoxyfurazan (FDNAF) was designed and synthesized via oxidation coupling, hydrolysis, bromization, reduction, nitration, salification and fluorination etc., and the structures of all the intermediates and the title compound were characterized by IR, 1H NMR, 13C NMR, 15N NMR、19F NMR and elemental analysis. Using HCl/CH3CH2OH as the hydrolysis system instead of AcCl/CH3OH, the condition of hydrolysis reaction was optimized, the reaction time was shortened from 18 h to 2 h and the purity of raw product was improved to 93%. The bromination reaction conditions were also studied. Under the optimum conditions with the temperature of 20℃ and the reaction time of 30 min, the brominated product was obtained with a yield of 51.5%. Based on B3LYP method of density function theory, 13C NMR, 15N NMR and IR chemical shifts were studied theoretically, which agreed with experimental data. The physicochemical properties, detonation performances and thermal behaviors of 3, 3'-bis(nitromethyl-ONN-azoxy)azoxyfurazan (BNMAF), 3, 3'-bis(dinitromethyl-ONN-azoxy)azoxyfurazan (BDNAF) and FDNAF were studied and analyzed. The results proved that FDNAF is a potential energetic compound with the theoretical density of 2.02 g·cm-3, the decomposition point of 233.4℃, the oxygen balance of 6.72%, the explosion velocity of 9735 m·s-1, the detonation pressure of 44.9 GPa, and the characteristic drop height of impact sensitivity of 36 cm.
2017, 37(10): 2745-2751
doi: 10.6023/cjoc201704001
Abstract:
A fluorination reaction of P(Ⅲ) compounds with the electrophilic fluorinating reagent Selectfluor is described. The reaction proceeded in acetonitrile/water at room temperature for 15~60 min to afford phosphoric fluorides in 34%~81% yields.
A fluorination reaction of P(Ⅲ) compounds with the electrophilic fluorinating reagent Selectfluor is described. The reaction proceeded in acetonitrile/water at room temperature for 15~60 min to afford phosphoric fluorides in 34%~81% yields.
2017, 37(10): 2752-2762
doi: 10.6023/cjoc201705002
Abstract:
A mycophenolic acid producing strain OUCMDZ-4920, identified as Penicillium brevicompactum, was isolated from a marine sediment (-68 m) collected in South China Sea by means of intergrated chemical and bioactive screening method. Eleven compounds including mycophenolic acid (3) and its seven analogues (1, 2 and 4~8) were isolated from a nutrient-poor fermentation broth of P. brevicompactum OUCMDZ-4920, among which (±)-brevicolides A (1) and B (2) were new compounds. On the bases of spectroscopic and electronic circular dichroism (ECD) analyses, chemical transformation, chiral separation and Mosher's method, new compounds (-)-brevicolide A (1a), (+)-brevicolide A (1b), (-)-brevicolide B (2a) and (+)-brevicolide B (2b) were identified as 7-hydroxy-6-((S)-2-hydroxy-2-((R)-2-methyl-5-oxotetrahydrofuran-2-yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((R)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran-2-yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((S)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran-2-yl)ethyl)-5-methoxy-4-methylisobenzo-furan-1(3H)-one and 7-hydroxy-6-((R)-2-hydroxy-2-((R)-2-methyl-5-oxotetrahydro-furan-2-yl)ethyl)-5-methoxy-4-methylisobenzo-furan-1(3H)-one, respectively. And the known compounds were identified as mycophenolic acid (3), 3-hydroxymycophenolic acid (4), (S)-4-(5-hydroxy-7-methoxy-4-methyl-1-oxo-1, 3-dihydroisobenzo-furan-6-yl)-2-methylbutanoic acid (5), norpestaphthalides A (6) and B (7), 5, 7-dihydroxy-4-methylisobenzofuran-1(3H)-one (8), 6, 8-dihydroxy-3-(hydroxymethyl)-1H-isochromen-1-one (9), brevianamides A (10) and E (11), respectively. Compound 3 displayed good cytotoxicities against murine leukemia P388 cell, human oral epithelial carcinoma KB cell, human colorectal cancer HT29 cell, human breast cancer MCF-7 cell, and human lung cancer A549 cell as well as good antifungal activity against Candida albicans with the IC50 values of 0.4~5.29 μmol·L-1, and a half maximal inhibitory concentration (MIC) value of 4.7 μmol·L-1, respectively. In addition, four new compounds, (-)-7-O-methylbrevicolide A (12a), (+)-7-O-methyl-brevicolide A (12b), (-)-7-O-methyl-brevicolide B (13a) and (+)-7-O-methylbrevicolide B (13b) were also synthesized.
A mycophenolic acid producing strain OUCMDZ-4920, identified as Penicillium brevicompactum, was isolated from a marine sediment (-68 m) collected in South China Sea by means of intergrated chemical and bioactive screening method. Eleven compounds including mycophenolic acid (3) and its seven analogues (1, 2 and 4~8) were isolated from a nutrient-poor fermentation broth of P. brevicompactum OUCMDZ-4920, among which (±)-brevicolides A (1) and B (2) were new compounds. On the bases of spectroscopic and electronic circular dichroism (ECD) analyses, chemical transformation, chiral separation and Mosher's method, new compounds (-)-brevicolide A (1a), (+)-brevicolide A (1b), (-)-brevicolide B (2a) and (+)-brevicolide B (2b) were identified as 7-hydroxy-6-((S)-2-hydroxy-2-((R)-2-methyl-5-oxotetrahydrofuran-2-yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((R)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran-2-yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((S)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran-2-yl)ethyl)-5-methoxy-4-methylisobenzo-furan-1(3H)-one and 7-hydroxy-6-((R)-2-hydroxy-2-((R)-2-methyl-5-oxotetrahydro-furan-2-yl)ethyl)-5-methoxy-4-methylisobenzo-furan-1(3H)-one, respectively. And the known compounds were identified as mycophenolic acid (3), 3-hydroxymycophenolic acid (4), (S)-4-(5-hydroxy-7-methoxy-4-methyl-1-oxo-1, 3-dihydroisobenzo-furan-6-yl)-2-methylbutanoic acid (5), norpestaphthalides A (6) and B (7), 5, 7-dihydroxy-4-methylisobenzofuran-1(3H)-one (8), 6, 8-dihydroxy-3-(hydroxymethyl)-1H-isochromen-1-one (9), brevianamides A (10) and E (11), respectively. Compound 3 displayed good cytotoxicities against murine leukemia P388 cell, human oral epithelial carcinoma KB cell, human colorectal cancer HT29 cell, human breast cancer MCF-7 cell, and human lung cancer A549 cell as well as good antifungal activity against Candida albicans with the IC50 values of 0.4~5.29 μmol·L-1, and a half maximal inhibitory concentration (MIC) value of 4.7 μmol·L-1, respectively. In addition, four new compounds, (-)-7-O-methylbrevicolide A (12a), (+)-7-O-methyl-brevicolide A (12b), (-)-7-O-methyl-brevicolide B (13a) and (+)-7-O-methylbrevicolide B (13b) were also synthesized.
2017, 37(10): 2655-2662
doi: 10.6023/cjoc201705014
Abstract:
The synthesis of carbazoles via Pd-catalyzed direct cross-coupling of indoles with in situ generated aryl vinyl ketones by using statured ketones as the olefins source is described. This protocol obviates the need for additional preparation steps of aryl vinyl ketones and therefore opens up a new door to synthesis of carbazoles in an atom-and step-economical fashion.
The synthesis of carbazoles via Pd-catalyzed direct cross-coupling of indoles with in situ generated aryl vinyl ketones by using statured ketones as the olefins source is described. This protocol obviates the need for additional preparation steps of aryl vinyl ketones and therefore opens up a new door to synthesis of carbazoles in an atom-and step-economical fashion.
2017, 37(10): 2678-2684
doi: 10.6023/cjoc201704049
Abstract:
A simple and efficient nickel-catalyzed oxidative halogenation (Cl, Br) of C(5) and C(7) C-H bond of 8-aminoquinoline amides has been developed. This method employed low-cost and easy availability nickel as catalyst and oxygen as oxidant. The reactions have good functional groups compatibility, giving highly selective C(5) and C(7) di-halogenated products in good to excellent yields.
A simple and efficient nickel-catalyzed oxidative halogenation (Cl, Br) of C(5) and C(7) C-H bond of 8-aminoquinoline amides has been developed. This method employed low-cost and easy availability nickel as catalyst and oxygen as oxidant. The reactions have good functional groups compatibility, giving highly selective C(5) and C(7) di-halogenated products in good to excellent yields.
2017, 37(10): 2763-2766
doi: 10.6023/cjoc201705035
Abstract:
Five clerodane diterpenes were isolated from the roots of Polyalthia laui during a systematic phytochemical investigation. Their structures were elucidated by the NMR and HRMS data as methyl (4→2)-abeo-2, 13-diformyl-cleroda-2, 12E-dien-15-ate (1), (E)-ent-cleroda-3, 12-diene-15, 16-dioic acid (2), 14, 15-dinorclerod-3-ene-2, 13-dione (3), solidagolactone (4), and 16-hydroxy-3, 13Z-kolavadien-16, 15-olide (5). Among them, compounds 1~2 are new clerodane diterpenes. Biological evaluation of compounds 1~5 against human Hela, A549, MCF-7 and HL-60 human cancer cell lines showed that all com-pounds displayed moderate cytotoxicities against various human cancer cell lines with IC50 ranged from 13.22 to 37.16 μmol/L.
Five clerodane diterpenes were isolated from the roots of Polyalthia laui during a systematic phytochemical investigation. Their structures were elucidated by the NMR and HRMS data as methyl (4→2)-abeo-2, 13-diformyl-cleroda-2, 12E-dien-15-ate (1), (E)-ent-cleroda-3, 12-diene-15, 16-dioic acid (2), 14, 15-dinorclerod-3-ene-2, 13-dione (3), solidagolactone (4), and 16-hydroxy-3, 13Z-kolavadien-16, 15-olide (5). Among them, compounds 1~2 are new clerodane diterpenes. Biological evaluation of compounds 1~5 against human Hela, A549, MCF-7 and HL-60 human cancer cell lines showed that all com-pounds displayed moderate cytotoxicities against various human cancer cell lines with IC50 ranged from 13.22 to 37.16 μmol/L.
2017, 37(10): 2767-2771
doi: 10.6023/cjoc201705009
Abstract:
A series of novel pyridine derivatives containing oxime esters have been synthesized from 3-methylpyridine, ethyl pivalate, hydroxylamine hydrochloride and substituted benzoic acid by addition, oximization and esterification reactions, which has the advantages of moderate reaction condition and high yield. Their structures were elucidated by IR, 1H NMR, 13C NMR and elemental analysis. Moreover, the target compounds were evaluated for their antifungal activity against two plant pathogens by the mycelium growth rate method. The results indicated that O-(4-bromobenzoyl)-3, 3-dimethyl-1-(pyridin-3-yl)butan-2-one oxime (3h) and O-(4-chlorobenzoyl)-3, 3-dimethyl-1-(pyridin-3-yl)butan-2-one oxime (3j) exhibited strong antifungal activity against S. sclerotiorum with EC50 values of 5.07 and 4.81 μg/mL, and 3h, 3j and O-(3, 4-dichlorobenzoyl)-3, 3-dimethyl-1-(pyridin-3-yl)butan-2-one oxime (3l) displayed high antifungal activity against B. cinerea with EC50 values of 4.98, 5.44 and 6.34 μg/mL, respectively.
A series of novel pyridine derivatives containing oxime esters have been synthesized from 3-methylpyridine, ethyl pivalate, hydroxylamine hydrochloride and substituted benzoic acid by addition, oximization and esterification reactions, which has the advantages of moderate reaction condition and high yield. Their structures were elucidated by IR, 1H NMR, 13C NMR and elemental analysis. Moreover, the target compounds were evaluated for their antifungal activity against two plant pathogens by the mycelium growth rate method. The results indicated that O-(4-bromobenzoyl)-3, 3-dimethyl-1-(pyridin-3-yl)butan-2-one oxime (3h) and O-(4-chlorobenzoyl)-3, 3-dimethyl-1-(pyridin-3-yl)butan-2-one oxime (3j) exhibited strong antifungal activity against S. sclerotiorum with EC50 values of 5.07 and 4.81 μg/mL, and 3h, 3j and O-(3, 4-dichlorobenzoyl)-3, 3-dimethyl-1-(pyridin-3-yl)butan-2-one oxime (3l) displayed high antifungal activity against B. cinerea with EC50 values of 4.98, 5.44 and 6.34 μg/mL, respectively.
2017, 37(10): 2772-2775
doi: 10.6023/cjoc201703007
Abstract:
Through a variety of chromatographic techniques and spectroscopic methods, sixteen diterpenes were isolated and identified from the ethanol extraction of the roots of Salvia kiaometiensis Lévl. Their structures were identified to be 6, 8, 11, 13-abietatetraen-12-ol dimer (1), kiaometin (2), miltirone (3), tanshinone ⅡA (4), crypotanshione (5), tanshindiol C (6), ferruginol (7), 2-isopropyl-8-methylphenanthrene-3, 4-dione (8), tanshinone I (9), trijuganone B (10), dihydrotanshinone I (11), grandifolias C (12), przewalskin (13), tanshinlactone (14), 6, 7, 8, 9-tetrahydro-1, 6, 6-trimethylfuro[3, 2-c]naphtha[2, 1-e]oxepine-10, 12-dione (15), and salmilalbanone (16). Compound 1 is a new abietane diterpenes dimer, and compound 2 is a new 7, 8:7, 20-diepoxy-nor-abietane diterpenes. All of the diterpenes were isolated from this plant for the first time.
Through a variety of chromatographic techniques and spectroscopic methods, sixteen diterpenes were isolated and identified from the ethanol extraction of the roots of Salvia kiaometiensis Lévl. Their structures were identified to be 6, 8, 11, 13-abietatetraen-12-ol dimer (1), kiaometin (2), miltirone (3), tanshinone ⅡA (4), crypotanshione (5), tanshindiol C (6), ferruginol (7), 2-isopropyl-8-methylphenanthrene-3, 4-dione (8), tanshinone I (9), trijuganone B (10), dihydrotanshinone I (11), grandifolias C (12), przewalskin (13), tanshinlactone (14), 6, 7, 8, 9-tetrahydro-1, 6, 6-trimethylfuro[3, 2-c]naphtha[2, 1-e]oxepine-10, 12-dione (15), and salmilalbanone (16). Compound 1 is a new abietane diterpenes dimer, and compound 2 is a new 7, 8:7, 20-diepoxy-nor-abietane diterpenes. All of the diterpenes were isolated from this plant for the first time.
2017, 37(10): 2776-2782
doi: 10.6023/cjoc201703013
Abstract:
Chiral spirooxindole γ-lactones with three stereogenic centres are rare. An efficient asymmetric construction of novel spiro-fused 2-oxindole/α-methy-paraconnic ester is reported, which was offered via organocatalytic Michael reaction of propaldehyde and olefinic oxindoles, with subsequent H2O2/K2CO3 system-mediated α-hydroxylation/hemiacetalization cascade reaction under oil/water two-phase conditions, and final oxidative γ-lactonization by pyridinium chlorochromate (PCC). The presented strategy features mild reaction conditions, excellent yields (91%~98%) and enatioselectiveties (87%~95%), and accordingly constitutes a facile and new method for the synthesis of chiral multisubstituted spirooxindole γ-lactones. All structures of new products were confirmed by 1H NMR, 13C NMR and HRMS techniques.
Chiral spirooxindole γ-lactones with three stereogenic centres are rare. An efficient asymmetric construction of novel spiro-fused 2-oxindole/α-methy-paraconnic ester is reported, which was offered via organocatalytic Michael reaction of propaldehyde and olefinic oxindoles, with subsequent H2O2/K2CO3 system-mediated α-hydroxylation/hemiacetalization cascade reaction under oil/water two-phase conditions, and final oxidative γ-lactonization by pyridinium chlorochromate (PCC). The presented strategy features mild reaction conditions, excellent yields (91%~98%) and enatioselectiveties (87%~95%), and accordingly constitutes a facile and new method for the synthesis of chiral multisubstituted spirooxindole γ-lactones. All structures of new products were confirmed by 1H NMR, 13C NMR and HRMS techniques.
