Login In
1993 Volume 4 Issue 6
1993, 4(6): 471-474
Abstract:
The insertion of dichlorocarbene generated from chloroform by Phase Transfer Catalysis (PTC) into carbon-boron bond of dialkylborate anions 3,obtained by method A and B,resulted in the formation of the intermediates 5,which were oxidized with alkaline hydrogen peroxide to give the corresponding dialkylketones in 36-77.9% yields.
The insertion of dichlorocarbene generated from chloroform by Phase Transfer Catalysis (PTC) into carbon-boron bond of dialkylborate anions 3,obtained by method A and B,resulted in the formation of the intermediates 5,which were oxidized with alkaline hydrogen peroxide to give the corresponding dialkylketones in 36-77.9% yields.
1993, 4(6): 475-478
Abstract:
The aldol condensation reactions of acetylferrocene with several aromatic aldehydes have been studied in the solid state.The results showed that they revealed different reactivities in the solid slate from that in solution and eight compounds have been prepared.Their structures have been characterized by UV,IR,1HNMR,HS and elemental analysis.
The aldol condensation reactions of acetylferrocene with several aromatic aldehydes have been studied in the solid state.The results showed that they revealed different reactivities in the solid slate from that in solution and eight compounds have been prepared.Their structures have been characterized by UV,IR,1HNMR,HS and elemental analysis.
1993, 4(6): 479-482
Abstract:
11β-Hydroxy-androst-4-en-3,17-dione (1a),androst-4,9 (11)-dien-3,17-dione-(2a),androst-4-en-3,11,17-trione (3a),11α-methoxy-androst-4-en-3,17-dione (4a) and 11β-metboxy-androst-4-en-3,17-dione (5a) were selectively reduced to the corresponding 17β-OH derivatives in one step without the protection of 3-oxo (and 11-oxo,in the case of 3a) group with the yields ranging from 65% to 79%.In these reactions,the ditute NaBH4 (or KBH4) solution in methanol was added dropwise to the 3,17-dioxo-steroids solution in methanol-benzene-pyridine,while the reaction mixtures were well stirred at -5~5℃.Acid (such as gtacial acetic acid) was added to quench the reactions.The resulted testosterone derivatives (1b~5b) were purified by flash chromatography.
11β-Hydroxy-androst-4-en-3,17-dione (1a),androst-4,9 (11)-dien-3,17-dione-(2a),androst-4-en-3,11,17-trione (3a),11α-methoxy-androst-4-en-3,17-dione (4a) and 11β-metboxy-androst-4-en-3,17-dione (5a) were selectively reduced to the corresponding 17β-OH derivatives in one step without the protection of 3-oxo (and 11-oxo,in the case of 3a) group with the yields ranging from 65% to 79%.In these reactions,the ditute NaBH4 (or KBH4) solution in methanol was added dropwise to the 3,17-dioxo-steroids solution in methanol-benzene-pyridine,while the reaction mixtures were well stirred at -5~5℃.Acid (such as gtacial acetic acid) was added to quench the reactions.The resulted testosterone derivatives (1b~5b) were purified by flash chromatography.
1993, 4(6): 483-484
Abstract:
First total synthesis of natural styryl-furone,(+)-7-epigoniofufurone 1,from D-glycero-D-gulo-heptono-γ-lactone in eight steps (13% overall) is described.The absolute stereochemistry of 1 is confirmed.
First total synthesis of natural styryl-furone,(+)-7-epigoniofufurone 1,from D-glycero-D-gulo-heptono-γ-lactone in eight steps (13% overall) is described.The absolute stereochemistry of 1 is confirmed.
1993, 4(6): 485-488
Abstract:
A series of compounds,which are structurally analogous to scopolamine and also in accordance with the general formula of neuroleptic benzamides,were synthesized and tested for their potential antipsychotic activity.
A series of compounds,which are structurally analogous to scopolamine and also in accordance with the general formula of neuroleptic benzamides,were synthesized and tested for their potential antipsychotic activity.
1993, 4(6): 489-492
Abstract:
Oxiranes as well as four and five membered rings of cyclic ethers were cleaved with acyl chloride in the presence of samarium trichloride or Eu (hfe)3 as Lewis-acid catalyst under mild conditions,the oorresponding chloroesters were obtained readily and smoothly in excellent yields.
Oxiranes as well as four and five membered rings of cyclic ethers were cleaved with acyl chloride in the presence of samarium trichloride or Eu (hfe)3 as Lewis-acid catalyst under mild conditions,the oorresponding chloroesters were obtained readily and smoothly in excellent yields.
1993, 4(6): 493-494
Abstract:
Optically active bicyclolactones 4 were prepared via a new simple route.
Optically active bicyclolactones 4 were prepared via a new simple route.
1993, 4(6): 495-496
Abstract:
5-Hydroxymethylfurfuraldehyde (HMF) was prepared from fructose or sucrose in high yield by using ZrCl4 or Cp2ZrCl2 as the catalyst under mild conditions.
5-Hydroxymethylfurfuraldehyde (HMF) was prepared from fructose or sucrose in high yield by using ZrCl4 or Cp2ZrCl2 as the catalyst under mild conditions.
1993, 4(6): 497-498
Abstract:
A polysaccharide,PS(1),has been isolated from the pollen of papaver somniferum.PS(1) is a highly branched arabinogalactan,which,mainly contains α-L-arabinofuranosyl(1→)and(3,6→1)-β-D-galactopyranosyl residues.We also studied the circular dichroism and immunoactivity of PS(1).
A polysaccharide,PS(1),has been isolated from the pollen of papaver somniferum.PS(1) is a highly branched arabinogalactan,which,mainly contains α-L-arabinofuranosyl(1→)and(3,6→1)-β-D-galactopyranosyl residues.We also studied the circular dichroism and immunoactivity of PS(1).
1993, 4(6): 499-500
Abstract:
Two new ceramides,Nephtixamide A and B,were isolated from the soft coral Nephthea tixierae verseveldt.Their structures were established by spectroscopic methods.
Two new ceramides,Nephtixamide A and B,were isolated from the soft coral Nephthea tixierae verseveldt.Their structures were established by spectroscopic methods.
1993, 4(6): 501-504
Abstract:
A new depside named salvianolic acid H was isolated from the aqueous extract of Salvia cavaleriei var.simplicifolia,along with salvianolic acid A,B,C,isosalvianolic acid C,lithospermic acid,rosmarinic acid,R-(+)-β-(3,4-dihydroxyphenyl) lacticacid and protocatechualdehyde.Rosmarinic acid was obtained as the major component.
A new depside named salvianolic acid H was isolated from the aqueous extract of Salvia cavaleriei var.simplicifolia,along with salvianolic acid A,B,C,isosalvianolic acid C,lithospermic acid,rosmarinic acid,R-(+)-β-(3,4-dihydroxyphenyl) lacticacid and protocatechualdehyde.Rosmarinic acid was obtained as the major component.
1993, 4(6): 505-506
Abstract:
The structure of a new macrocyclic compound,clemochinenoside B,isolated from the root of Clematis chinensis was elucidated by means of NMR,FAB-MS,NOE and chemical hydrolysis.
The structure of a new macrocyclic compound,clemochinenoside B,isolated from the root of Clematis chinensis was elucidated by means of NMR,FAB-MS,NOE and chemical hydrolysis.
1993, 4(6): 507-510
Abstract:
The porphyrin-like macrocycles and their metal complexes are a novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient processes.
The porphyrin-like macrocycles and their metal complexes are a novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient processes.
1993, 4(6): 511-512
Abstract:
Some Schiff-base cobalt(Ⅱ) chelates like ethylenebis [(2-hydroxy-3-methoxy-5-methylphenyl)methylideneiminato]Cobalt(Ⅱ) were coordioatively anchored onto poly (4-vinylpyridine-co-styrene) in diglyme solution and the dioxygen-affinity of the resulting polymeric complexes were measured in situ.
Some Schiff-base cobalt(Ⅱ) chelates like ethylenebis [(2-hydroxy-3-methoxy-5-methylphenyl)methylideneiminato]Cobalt(Ⅱ) were coordioatively anchored onto poly (4-vinylpyridine-co-styrene) in diglyme solution and the dioxygen-affinity of the resulting polymeric complexes were measured in situ.
1993, 4(6): 513-516
Abstract:
The reacdynamics on Ba+BrCH3→BaBr+CH3 has been investigated in the first proposed potential energy surface of the generalized LEPS type,using the quasiclassical trajectory method.In simulation of the conditions in molecular beam experiments,the results of the present study show significant effect of the reagent collision energy on the dynamics of the reaction,and are in good agreement with the experimental ones.
The reacdynamics on Ba+BrCH3→BaBr+CH3 has been investigated in the first proposed potential energy surface of the generalized LEPS type,using the quasiclassical trajectory method.In simulation of the conditions in molecular beam experiments,the results of the present study show significant effect of the reagent collision energy on the dynamics of the reaction,and are in good agreement with the experimental ones.
1993, 4(6): 517-520
Abstract:
The NaI and IF product rotational alignment of the reactions of Na,F+CH3I has been theoretically studied in a LEPS PES.The product alignment versus the relative translational energy of the reactants has been obtained.
The NaI and IF product rotational alignment of the reactions of Na,F+CH3I has been theoretically studied in a LEPS PES.The product alignment versus the relative translational energy of the reactants has been obtained.
1993, 4(6): 521-522
Abstract:
This paper reports a new approach to estimate kinetic parameters for the thermal decomposition of the solid state from TG-DTG or DSC curve.Reduced equations are derived for the first tlme.The validity of these equations was demonstrated employing data obtained from the dehydration process of calcium oxalate monohydrate.
This paper reports a new approach to estimate kinetic parameters for the thermal decomposition of the solid state from TG-DTG or DSC curve.Reduced equations are derived for the first tlme.The validity of these equations was demonstrated employing data obtained from the dehydration process of calcium oxalate monohydrate.
1993, 4(6): 523-526
Abstract:
[Ni(TIM)]2+ can act as a catalyst in bromate-gallic acid-sulfuric acid system to produce sequential oscillations have been studied.When bromate solution is added to the reaction mixture,two sets of concentration oscillations take place,the first set is the noncatalyzed oscillation and the second is [Ni(TIM)]2+ catalyzed oscillation.
[Ni(TIM)]2+ can act as a catalyst in bromate-gallic acid-sulfuric acid system to produce sequential oscillations have been studied.When bromate solution is added to the reaction mixture,two sets of concentration oscillations take place,the first set is the noncatalyzed oscillation and the second is [Ni(TIM)]2+ catalyzed oscillation.
1993, 4(6): 527-530
Abstract:
For the first time,fullerenes are applied to the study on the interface between two immisible electrolyte solutions.Experiments show they are a new kind of inhibitors.Obvious inhibitive behavior to the TMA+ transfer across the water/nitrobenzene interface is observed.
For the first time,fullerenes are applied to the study on the interface between two immisible electrolyte solutions.Experiments show they are a new kind of inhibitors.Obvious inhibitive behavior to the TMA+ transfer across the water/nitrobenzene interface is observed.
STUDIES ON THE VOLTAMMETRIC BEHAVIOR OF EU(Ⅲ)-ALDOPENTOSE AND EU(Ⅲ)-D-RIBOSE-L-AMINO ACIDS COMPLEXES
1993, 4(6): 531-534
Abstract:
The rate of voltammetric reduction of Eu(Ⅲ) in acetate solution was increased by the formation of a complex with ribose,lyxose or arabinose.If a ternary complex of Eu(Ⅲ)-D-ribose-L-phenylanaline formed on the surface of mercury electrode,the redox process of Eu(Ⅲ) became more reversible than that of Eu(Ⅲ)-D-ribose in solution phase.
The rate of voltammetric reduction of Eu(Ⅲ) in acetate solution was increased by the formation of a complex with ribose,lyxose or arabinose.If a ternary complex of Eu(Ⅲ)-D-ribose-L-phenylanaline formed on the surface of mercury electrode,the redox process of Eu(Ⅲ) became more reversible than that of Eu(Ⅲ)-D-ribose in solution phase.
1993, 4(6): 535-536
Abstract:
The immobilization of SiW12O404--in poly (4-aminoazobenzene) film was done by electrochemical method.According to the continuous cyclic voltammograms of the modified electrode,it can be determined that SiW12O404--in the polymer is very stable.The paper reports the elecctrochemical properties of the modified electrode,Moreover,it was found that the modified electrode exhibits electrocatalysis for the reaction of oxygen.
The immobilization of SiW12O404--in poly (4-aminoazobenzene) film was done by electrochemical method.According to the continuous cyclic voltammograms of the modified electrode,it can be determined that SiW12O404--in the polymer is very stable.The paper reports the elecctrochemical properties of the modified electrode,Moreover,it was found that the modified electrode exhibits electrocatalysis for the reaction of oxygen.
1993, 4(6): 537-540
Abstract:
The electronic structure of (C5H5)aCe(OCMea) have been studied by INDO method.Some interesting results hays been obtained.
The electronic structure of (C5H5)aCe(OCMea) have been studied by INDO method.Some interesting results hays been obtained.
1993, 4(6): 541-542
Abstract:
In the paper,the structures of the crystalline 3,4-polyisoprene (3,4-PI) which was first synthesized in our institute,were investigated by using Wide Angle X-ray Diffraction (WAXD);Small Angle X-ray Scattering (SAXS) and Laue photography in various polymerization conditions and elongate ratios.It was found that reducing reaction velocity was favourable for crystalline capacity.The polymeric structures were dependent mainly on nitrogen electron donor.The degree of crystallinity and long period were increased with elongate ratio,but crystalline size was decreased.The polymers used in the work belong to inhomogeneous particulate system.The particulate radii were between 35-164A.
In the paper,the structures of the crystalline 3,4-polyisoprene (3,4-PI) which was first synthesized in our institute,were investigated by using Wide Angle X-ray Diffraction (WAXD);Small Angle X-ray Scattering (SAXS) and Laue photography in various polymerization conditions and elongate ratios.It was found that reducing reaction velocity was favourable for crystalline capacity.The polymeric structures were dependent mainly on nitrogen electron donor.The degree of crystallinity and long period were increased with elongate ratio,but crystalline size was decreased.The polymers used in the work belong to inhomogeneous particulate system.The particulate radii were between 35-164A.
1993, 4(6): 543-546
Abstract:
The catalytic hydrogenation of magnesium under atmospheric pressure has been optimized so that the reaction can be completed within seven hours. The resulted magnesium hydride is in the form of superfine powder with an average primary particle size of 15 nm. This magnesium hydride exhibits higher dehydrogenation/hydrogenation rates than that obtained under pressure with the same catalyst system.
The catalytic hydrogenation of magnesium under atmospheric pressure has been optimized so that the reaction can be completed within seven hours. The resulted magnesium hydride is in the form of superfine powder with an average primary particle size of 15 nm. This magnesium hydride exhibits higher dehydrogenation/hydrogenation rates than that obtained under pressure with the same catalyst system.
1993, 4(6): 547-550
Abstract:
A new mixed heteropoly acid,α-H5[GeW9Mo2VO40]·22H2O,bas been prepared and characterized by means of ICP,potentiometric titration,IR and UV spectra,X-ray powder diffraction and thermal analysis.
A new mixed heteropoly acid,α-H5[GeW9Mo2VO40]·22H2O,bas been prepared and characterized by means of ICP,potentiometric titration,IR and UV spectra,X-ray powder diffraction and thermal analysis.
1993, 4(6): 551-554
Abstract:
A new rare-earth vanadate LaBa2V3O11 is synthesized by the conventional solid state reaction.The single phase can be obtained at sintering temperature of 1010℃. The X-ray powder diffraction shows that the new compound has tetragonal structure with cell parameters a of 7.94 and c of 24.27 Å The LaBa2V3O11 can be decomposed to LaVO4.Ba3(VO2)2 and V2O5 by higher sitering temperature than 1010℃.The as-sintered sample is insulator with resistivity of 1012 ohm cm.Furthermore,if the as-sintered sample was annealed under H2 atmosphere,the LaBa2V3O11 decomposed to LaVO3 and BaYO4 despite ofthe lower annealing temperature of 950℃.
A new rare-earth vanadate LaBa2V3O11 is synthesized by the conventional solid state reaction.The single phase can be obtained at sintering temperature of 1010℃. The X-ray powder diffraction shows that the new compound has tetragonal structure with cell parameters a of 7.94 and c of 24.27 Å The LaBa2V3O11 can be decomposed to LaVO4.Ba3(VO2)2 and V2O5 by higher sitering temperature than 1010℃.The as-sintered sample is insulator with resistivity of 1012 ohm cm.Furthermore,if the as-sintered sample was annealed under H2 atmosphere,the LaBa2V3O11 decomposed to LaVO3 and BaYO4 despite ofthe lower annealing temperature of 950℃.
1993, 4(6): 555-558
Abstract:
A mixed Langmuir-Blodgett film was built up by mixture 1:1 of bis (ethyldithio) tetrathiafulvalene-tetracyanoquinodimethane/stearie acid(BEDT-TTF-TCNQ/SA).A degree of charge transfer(CT)in complex of BEDT-TTF with TCNQ was estimated at 0.477~0,486 by Raman frequencies of central Vc=c and Vc-s,The existence of charge transfer in BEDT-TTF-TCNQ has been confirmed by FTIR and XPS spectroscopy.
A mixed Langmuir-Blodgett film was built up by mixture 1:1 of bis (ethyldithio) tetrathiafulvalene-tetracyanoquinodimethane/stearie acid(BEDT-TTF-TCNQ/SA).A degree of charge transfer(CT)in complex of BEDT-TTF with TCNQ was estimated at 0.477~0,486 by Raman frequencies of central Vc=c and Vc-s,The existence of charge transfer in BEDT-TTF-TCNQ has been confirmed by FTIR and XPS spectroscopy.
1993, 4(6): 559-560
Abstract:
Epitaxial crystallization of low-density polyethylene (LDPE) on highly oriented isotactic polypropylene (iPP) has been studied by electron microscopy.The results obtained by bright field (BF) electron microscopy and electron diffraction indicate that the LDPE can epitaxially grow on iPP substrate and form cross-hatched lamellae texture.The c axes of LDPE are ±50°apart from the c axes of iPP.The contact plane of two crystals is (010) of iPP and (100) of LDPE.
Epitaxial crystallization of low-density polyethylene (LDPE) on highly oriented isotactic polypropylene (iPP) has been studied by electron microscopy.The results obtained by bright field (BF) electron microscopy and electron diffraction indicate that the LDPE can epitaxially grow on iPP substrate and form cross-hatched lamellae texture.The c axes of LDPE are ±50°apart from the c axes of iPP.The contact plane of two crystals is (010) of iPP and (100) of LDPE.
1993, 4(6): 561-562
Abstract:
The title compound was prepared and characterized.Its crystal Structurewas determined by X-ray diffraction analysis,and consists of segregated cation and anion stacks in the perpendicular directions.Crystal data:monoclinic, P21/c,Mr=765.21,a=7.882(2)Å,b=15.526(4)Å,c=13.736(2)Å,β=99.87(2)0,V=1656.0(6)Å3,Dc=1.53g/cm3,Z=2,F(000)=780,R=0.040 and Rw=0.056.
The title compound was prepared and characterized.Its crystal Structurewas determined by X-ray diffraction analysis,and consists of segregated cation and anion stacks in the perpendicular directions.Crystal data:monoclinic, P21/c,Mr=765.21,a=7.882(2)Å,b=15.526(4)Å,c=13.736(2)Å,β=99.87(2)0,V=1656.0(6)Å3,Dc=1.53g/cm3,Z=2,F(000)=780,R=0.040 and Rw=0.056.
1993, 4(6): 561-562
Abstract:
In this work,the influence of heat treatment on Polyamide-1010 structure of aggregation state was studied by using WAXD and SAXS techniques.The results showed that the best crystallinity was obtained nearby T=175℃ for Polyamide-1010 samples with various annealing treatment.Through extrapolating method,the Tg obtained was approximately 58℃.Based on the one-dimensional electron density correlation function of partially crystalline polymers,some structural parameters of Polyamide-1010 were determined by SAXS.
In this work,the influence of heat treatment on Polyamide-1010 structure of aggregation state was studied by using WAXD and SAXS techniques.The results showed that the best crystallinity was obtained nearby T=175℃ for Polyamide-1010 samples with various annealing treatment.Through extrapolating method,the Tg obtained was approximately 58℃.Based on the one-dimensional electron density correlation function of partially crystalline polymers,some structural parameters of Polyamide-1010 were determined by SAXS.
