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1.
The lanthanum-substituted polyoxometalate [{La(CH3COO)(H2O)2( 2-P2W17O61)}2]16– (1) and the neodymium-substituted species [{Nd(H2O)3( 2 -P2W17O61)}2]14– (2) have been synthesized and characterized by IR spectroscopy and elemental analysis. Single-crystal X-ray analysis was carried out on K16[{La(CH3COO)(H2O)2( 2 -P2W17O61)}2]36H2O, which crystallizes in the triclinic system, space group P¯1, with a=12.3863(6) Å, b=12.8934(6) Å, c=31.7285(14) Å, =84.2000(10)°, =81.2300(10)°, =61.6500(10)°, and Z=1; K6.5Nd2.5[{Nd(H2O)3( 2-P2W17O61)}2]55H2O, which crystallizes in the monoclinic system, space group P2 1 /n, with a=17.5030(9) Å, b=23.7842(12) Å, c=19.1869(10) Å, =100.6610(10)°, and Z=1. The head-on, trans-oid dimer 1 consists of two ( 2 -P2W17O61)10– fragments connected by a lanthanum-acetate dimer, (La2(CH3COO)2(H2O)4)4+. Each La3+ ion is nine-coordinated in a monocapped, square-antiprismatic fashion. The neodymium-derivative 2 is also a trans-oid dimer, but the mode of binding is different from 1 and is best described as side-on. Each Nd3+ ion is eight-coordinated in a square-antiprismatic fashion with three terminal water molecules.  相似文献   

2.
Activation parameters of the interconversion of geometric isomers6a and6b were determined by a complete lineshape analysis of the temperature-dependent13C NMR spectra of 7,8-dipropyl-7-borabicyclo[4.2.2]deca-2,4,9-triene (6). For the reaction6a 6b, G 298 = 52.2±0.1 kJ mol–1, H = 27.9±0.5 kJ mol–1, S = –82±8 J mol–1 K–1; For the reaction6b 6a, G 298 = 52.6±0.1 kJ mol–1, H = 24.7±0.5 kJ mol–1, S = –93±10 J mol–1 K–1. The interconversion of deuteropyridine complexes9a and9b proceedsvia their dissociation, which indicates that the rearrangement of borane6 occurs according to the [1,3]-B shift mechanism.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2243–2250, September, 1996.  相似文献   

3.
Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH2Cl2 (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H2O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.
Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase
Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH2Cl2 (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H2O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.
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4.
Studies of the interaction of hydrotrioxides ROOOH of ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1,1-dimetoxyethane, 1,1-diethoxyethane, benzaldehyde and tetrahydrofuran with trimethyl triisopropyl, tributyl, triallyl, triphenyl and tri-o-chresyl phosphites (RO)3P have revealed that in mild conditions ROOOH rapidly and selectively oxidizes (RO)3P to the corresponding phosphates. The reaction stoichiometry has been established. Aromatic phosphites are shown to be of inferior reactivity to ROOOH as compared with aliphatic phosphites.
, 1-, 2-, 1-, 2-, 1,1-, 1,1-, -, -, -, -, -, -, -- (RO)3P. ROOOH (RO)3P . . , ROOOH .
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5.
Differential thermal and phase X-ray analyses have shown that MoO3 and Fe2V4O13 form a solid substitution solution, in which Mo6+ ions are incorporate into the crystal lattice of Fe2V4O13 in place of V5+ ions. The solubility limit of MoO3 in Fe2V4O13 at ambient temperature is 18 mole % of MoO3. The phase equilibria in the system Fe2V4O13-FeVMoO7, were also studied. Results are presented in the form of a phase diagram.
Zusammenfassung Durch DTA und Röntgenphasenanalyse wurde gezeigt, daß MoO3 und Fe2V4O13 Substitutionsmischkristalle bilden, in denen Mo6+-Ionen anstelle von V5+-Ionen in das Kristallgitter von Fe2V4O13 eingebaut sind. Die Löslichkeitsgrenze von MoO3 in Fe2V4O13 beträgt bei Umgebungstemperatur 18 Mol-% MoO3. Ebenfalls wurden die Phasengleichgewichte im System Fe2V4O13-FeVMoO7 untersucht. Die Ergebnisse sind in Form eines Phasendiagramms dargestellt.

- , 3 Fe2V4O13 , o6+ V5– Fe2V4O13. 3 Fe2V4O13 18 %. Fe2V4O13-FeVMoO7 .
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6.
The title metallocenium salts form crystalline 2:1 host:guest inclusion compounds with-cyclodextrin, [(5-C5H5)2M]PF6 · 2-CD · 8H2O (1, M = Fe;2, M = Co;3, M = Rh). The X-ray crystal structures of1 and3, and the lattice constants, crystal system and space group of2 have been determined. Crystal data: triclinic, space groupP1 (No. 1),Z = 1;1,a = 13.865 (2) Å,b = 13.839 (2) Å,c = 15.520 (2) Å, = 91.43 (2)°, = 85.81 (2)°, = 120.22 (2)°, andR F = 0.089 for 4257 observed MoK reflections [I > 3(I)];2,a = 13.810 (2) Å,b = 13.872 (2) Å,c = 15.560 (2) Å, = 93.99 (2)°, = 87.06 (2)°, = 120.04 (2)°;3,a = 13.756 (1) Å,b = 13.863 (1) Å,c = 15.561 (2) Å, =94.39 (1)°, = 86.92 (1)°, = 119.89 (1)°, andR F = 0.061 for 11142 observed MoK reflections [I > 3(I)]. In the crystals of1 and3, two -cyclodextrin molecules are arranged head-to-head to form a dimer by means of intermolecular hydrogen bonding across the secondary hydroxyl faces of adjacent -CD monomers. The dimers are stacked along the crystallographicc axis to form a channel-type structure. The metallocenium cation is encapsulated within the cavity of the dimer, while the PF 6 anion is located outside the cavity, being centered between the primary hydroxyl faces of adjacent dimers. Eight water molecules of hydration per asymmetric unit reside in the spaces between the -CD columns. In view of the almost identical crystal data for2 a similar structure can be assumed for the cobaltocenium adduct.  相似文献   

7.
By the condensation of -halogenomethyl derivatives of pyrroles with -unsubstituted pyrroles the synthesis of the following unsymmetrical dipyrrolylmethanes has been effected: 5-benzyloxycarbonyl-5-ethoxycarbonyl-3, 3-di(-methoxycarbonylethyl)-4,4-dimethyl-2,2-dipyrrolylmethane (IIIa), 5-benzyloxycarbonyl-5-ethoxycarbonyl-3-(-methoxycarbonylethyl)-4, 4-diniethyl-3-n-propyl-2,2-dipyrrolylmethane(IIIb), 3-acetyl-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIIc), and 3-bromo-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIId). Hydrogenation of the unsymmetrical dipyrrolylmethanes IIIa, b, c, and d has given the corresponding monocarboxylic acids IVa, b, c, and d. The formylation of the dipyrrolylmethanemonocarboxylic acid IVa has given 5-ethoxycarbonyl-5-formyl-3,3-di(-methoxycarbonylethyl)-4, 4-dimethyl-2,2-dipyrrolylmethane (V).For communication II, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp. 1045–1047, August, 1970.  相似文献   

8.
The tetranuclear Au(I) pyrazolate complex, [(dppm)2Au4(3,5-Ph2Pz)2](NO3)2  H2O, 1, has been synthesized and structurally characterized. It is the first tetranuclear pyrazolate of Au(I) to have been found, although the trinuclear pyrazolates of Au(I) are well known. Complex 1 exhibits luminescence at 77 K when excited at 333 nm with an emission maximum at 454 nm. The emission has been assigned to ligand to metal charge transfer, LMCT, based upon the vibronic structure that is observed. The complex crystallizes in the monoclinic space group P21/c, with a=19.33(3) Å, b=20.26(3) Å, c=19.80(3) Å, =106.74(2)°, V=7425(17) Å3, Z=8, and R=0.058. The Au    Au distances are Au(1)    Au(4)=3.185(3) Å, Au(1)    Au(2)=3.230(3) Å, Au(2)    Au(3)=3.079(3) Å, and Au(3)    Au(4)=3.280(3) Å.  相似文献   

9.
By reacting the K, Rb, Cs, or Tl carbonates with excess phosphoric acid, crystals of superacid phosphites, namely, (RbH2PO3)2· H3PO3(I), (TlH2PO3)2· H3PO3(II), KH2PO3· H3PO3(III), -CsH2PO3· H3PO3(IV), and -CsH2PO3· H3PO3(V), were synthesized. Their structures were determined by single-crystal X-ray diffraction analysis at 150 K. Crystals I: triclinic system, space group , a= 7.713(2) Å, b= 8.679(3) Å, c= 9.235(3) Å, = 79.36(3)°, = 67.60(2)°, = 88.13(3)°, R 1= 0.0252; crystals II: triclinic system, space group , a= 7.690(3) Å, b= 8.494(3) Å, c= 9.292(4) Å, = 79.48(3)°, = 66.72(3)°, = 85.45(3)°, R 1= 0.0485; crystals III: monoclinic system, space group P21/c, a= 8.726(3) Å, b= 12.182(4) Å, c= 6.354(2) Å, = 104.14(3)°, R 1= 0.0241; crystals IV: orthorhombic system, space group P212121, a= 6.033(1) Å, b= 6.444(1) Å, c= 18.345(4) Å, R 1= 0.0172; crystals Vare monoclinic, space group C2/c, a= 9.990(3) Å, b= 12.197(4) Å, c= 6.866(2) Å. = 118.14(3)°, R 1= 0.0181. The hydrogen bonding systems form corrugated bands (Iand II), bent layers (III), individual tubes with rectangular cross sections (V), or a three-dimensional framework (IV). A comparative analysis of the crystal structures of acid phosphites with different compositions was performed.  相似文献   

10.
The reactions between trans-[OsVIO2Cl2L2] (L = PPh3, AsPh3, SbPh3) and carboxylic acids RCO2H (R = CH3, C(CH3)3, CH2Cl, CCl3, CF3) are studied. The resulting binuclear compounds were found to have the general formula [Os2 IV(-O)(-O2CR)2Cl4(L)2] (L = PPh3; R = CH3, C(CH3)3, CH2Cl, CCl3, CF3, and L = AsPh3; R = CH3, CH2Cl, CCl3, CF3). X-ray diffraction analysis revealed that the [Os2 IV(-O)(-O2CCCl3)2Cl4(PPh3)2] · CH2Cl2 complex crystallizes in a triclinic system with space group P ; a = 10.747(2) Å, b = 19.291(4) Å, c = 24.614(5) Å, = 100.08(3)°, = 90.63(3)°, = 97.05(3)°, V = 4983.5(17) Å3, Z = 4. The Os(-O)Os angle is 142.2(7)°. The interaction of trans-[OsVIO2Cl2(SbPh3)2] with all the acids under study is attended by intramolecular redox reaction resulting in SbCl2Ph3.  相似文献   

11.
Crown amide (1) forms a stoicheiometric 1:1 inclusion complex with water, the X-ray crystal structure of which is reported. Crystals of1 · H2O are triclinic, space groupP1, witha=7.503(1),b=11.394(3),c=13.443(2) Å, =107.066(18), =96.627(10), =106.377(14)°, andZ=2.R F =0.039 for 1697 MoK reflections [I>3(I)] measured at 24°C. The structure features a hydrogen bonded hostguest relationship with concrete1 · H2O units. Hydrogen bonds are between the water oxygen and O(4), N(4), respectively. The crystal packing shows a cavity arrangement of four ligands around each water molecule. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82055 (16 pages).  相似文献   

12.
Six kinds of tetra alkylester type calix[4]arene derivatives, (R1=R2=CH31, C2H52, C3H73,n-C4H94,t-C4H95,n-C10H216), a diethyl-didecyl mixed ester type (R1=C2H5, R2 =C10H217), and three kinds of lower rim bridged types (R1=C2H5, R2–R2=(CH2)108, (CH2)129, (CH2)2(OCH2CH2)310) were characterized by electrochemical measurement to elucidate the effect of the length of the alkyl group of alkoxycarbonyl substituents on Na+ selectivity. To obtain excellent Na+ selective ionophores, introduction of short chain alkyl groups rather than long chain ones, such as a decyl group, and maintenance of sufficient solubility of the calix[4]arene derivatives in the membrane solvent are required concurrently. Among the calix[4]arenes tested, 25,26,27,28-tetrakis[(ethoxycarbonyl)methoxy]-p-tert-butylcalix[4]arene2, and the diethyl-didecyl mixed ester type derivative7 are the best ionophores for a Na+ selective electrode. On the other hand, sodium selectivity of the bridged type derivative9 is comparable or even superior to that of the known bis(12-crown-4).This paper is dedicated to the commemorative issue on the 50th anniversary of calixarenes.  相似文献   

13.
Addition of phenylhydrazine to a mixture of VCl3 · THF/N,N-propyl-bis (salicyladimine) and sodium hydride yielded a trinuclear vanadium complex, V3(3-O)(-Cl)Cl6(-1-1PhNHNH2)2(PhNHN H2)2(THF), containing two bridging and two terminal phenylhydrazine ligands. The product has been crystallographically characterized (P21/n, a=12.949(2) Å,b=24.061(4) Å,c=22.504(4) Å, =107.22(1) deg.,V=6697(2) Å3 withZ=4) and was found to contain the first example of bridging monosubstituted hydrazine (phenylhydrazine) ligands.  相似文献   

14.
Crystals of the [(H3NCH2CCCCCH2NH3)]Cu2Cl4 -complex, formed in the oxidative dimerization of propargylammonium cations, were obtained by ac electrochemical synthesis from CuCl2 · 2H2O and propargylammonium chloride ([CCCH2NH3]Cl) and studied by X-ray diffraction analysis (DARCh automated diffractometer, MoK radiation, /2 scan mode; 2275 reflections with F 4(F), R = 0.048). Crystals are monoclinic: space group B2/b, a = 19.591(6) Å, b = 7.299(3) Å, c = 8.636(3) Å, = 106.83(3)°, Z = 4. The structure consists of individual [(H3NCH2CCCCCH2NH3)]Cu2Cl4 moietes united through the elongated Cu···Cl contacts (2.827(5) Å) into chains oriented along the [010] direction. The bond of the centrosymmetric propargylammonium dimer is -coordintated by copper(I) atom and is elongated to 1.227(6) Å.  相似文献   

15.
The structures of the 1:2 molecular complexes of trans -9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with acetophenone (1), (C26H20O2·2 C8H8O) and with 3-methylcyclopentanone (2), (C26H20O2·2C6H10O) have been determined by X-ray crystallography. The crystal data are as follows: Compound (1):P ,a =8.979(5) Å,b =9.316(3) Å,c = 11.12(1) Å, =94.40(6)°, = 106.53(6)°, = 109.92(5)°,V = 822.94 Å3,Z = 1,R = 0.097 for 2549 unique reflections. Compound (2):P ,a = 8.958(7) Å,b =9.815(4) Å,c = 9.807(4) Å, = 96.88(3)°, = 109.21(8)°, = 103.33(7)°,V = 774.10 Å3,Z = 1,R = 0.059 for 2494 unique reflections. The intermolecular arrangements in both structures are characterised by host-to-guest hydrogen bonding interactions. The thermal properties of compound (2) have been characterised by DTA and TGA thermograms.  相似文献   

16.
Bond strengths in RO-OOR, ROO-OH, and ROO-OOR (R, R = H, Me, Et, and Bu) molecules, calculated by the semiempirical quantum-chemical methods, were used to determine the enthalpies of formation of polyoxides RO x R (x = 3, 4) and related radicals and the bond strengths (D/kcal mol–1) in these molecules:D(ROOO-OR) = 33.2±0.9,D(ROOO-OH) = 37.5±0.7,D(R-O x R) = 76.0±1.2,D(H-000) = 58.6,D(R-000) = 42.8±0.8. A new value of Benson's polyoxide thermochemical increment, f H°[O-(O)2] = 11.1±1.0 kcal mol–1, was suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2190–2193, September, 1996.  相似文献   

17.
The paper presents results of the experimental determination of the quantity of heat liberated during the thermoluminesence (TL) of natural calcite.As the method for experimental investigation, quantitative differential thermal analysis was used, in which the reference was natural calcite which had previously been thermally treated at 623 K for 60 min to eliminate the TL effect.It was established that during the TL of natural calcite 7.11 J/g is liberated, which is in accordance with results obtained by estimating possible values of the concentration of charge carriers at trapping centers and the energy liberated by elementary recombination process.
Zusammenfassung Die Ergebnisse der experimentellen Bestimmung der während des TL-Prozesses von natürlichem Calcit freigesetzten Währmemenge werden vorgestellt.Bei den Versuchen wurde die quantitative Differentialthermoanalyse mit natürlichem Calcit als Referenzsubstanz eingesetzt, welcher vorher bei 623 K 60 Minuten zur Eliminierung des TL-Effekts thermisch behandelt worden war.Es wurde festgestellt, dass während des TL-Prozesses von natürlichem Calcit 7.11 J/g freigesetzt wurden. Dies stimmt mit den durch Schätzung der möglichen Konzentrationswerte der Änderungsträger in den Einschlusszentren und der durch elementare Rekombinationsprozesse freigesetzten Energie erhaltenen Ergebnissen überein.

, . , , 60 . 623 . , 7.11 / , , .
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18.
The cluster complex, Re6( 3-Se)8(PEt3)5(4-vinylpyridine)(SbF6)2 (1), featuring the face-capped octahedral Re6( 3-Se)82+ cluster core and site-differentiating triethylphosphine and 4-vinylpyridine ligands has been synthesized and structurally characterized. The complex crystallized in monoclinic space group P21 with a=11.748(1)Å, b=15.1212(2)Å, c=19.941(2)Å, =90°, =94.411(3)°, =90°, V=3531.8(7)Å3, Z=2, R1=0.0531, wR2=0.0774. Copolymerization of styrene with 1 via the polymerizable 4-vinylpyridine ligand afforded a novel inorganic-organic hybrid composite of high molecular weight and a low polydispersity index. Structural integrity of the cluster building block is maintained upon hybrid formation.  相似文献   

19.
Benzophenone analog 3 has been synthesized and characterized by the X-ray diffraction (XRD) method. The compound crystallizes in a monoclinic space group P21/c with cell parameters a = 7.701(8) Å, b = 7.151(5) Å, c= 28.323(3) Å, = 104.639(4)°, Z = 4. The structure exhibits intra- and intermolecular hydrogen bonding of the type N–HO, C–HO, and N–HN. The molecules are interlinked through hydrogen bonds forming an infinite chain. This polymeric-like structure may play an important role in biological activity.  相似文献   

20.
Zusammenfassung Durch Umsetzung von ,-Dichloracetophenon mit überschüss. prim. Amin und Schwefel in äther. Lösung unter Zusatz von K2CO3 (Reaktionszeit 140 Stdn., Reaktionstemp. max. 20°) können N,N-disubstituierte -Iminophenylglyoxylsäurethionamide (1–3) in guten Ausbeuten synthetisiert werden.-Iminoglyoxylsäurethionamide (4–6), die am Imin- bzw. Aminstickstoff auch unterschiedlich substituiert sein können (4, 6), erhält man aus den entsprechenden Phenylglyoxylsäurethionamiden durch Umsetzung mit überschüss. primären Aminen.Die -Iminophenylglyoxylsäurethionamide können bereits bei Raumtemp. glatt durch H2S zu den entsprechenden Phenylessigsäurethionamiden reduziert werden.
Synthesis of N,N-disubstituted -iminophenyl-thioglyoxylic amides, and their reduction by means of H2S to phenyl-thioacetic amides (Willgerodt—Kindler reaction, V.)
N,N-Disubstituted -iminophenylthioglyoxylamides (1–3) can be synthesized in good yields by the reaction of ,-dichloroacetophenone with excess primary amine and sulphur in eth. solution in the presence of potassium carbonate (reaction period 140 hours, reaction temperature max. 20°C).-Iminothioglyoxylamides (4–6), which may be differently substituted at the imine and amine nitrogen atoms (4, 6), may be obtained from the corresponding phenylthioglyoxylamides by reaction with an excess of primary amines.The -iminophenylthioglyoxylamides can be reduced smoothly at room temperature by hydrogen sulphide to the corresponding phenylthioacetamides.


4. Mitt.:F. Asinger, A. Saus undA. Mayer, Mh. Chem.98, 825 (1967).

Vgl. auchF. Asinger undH. Offermanns, Angew. Chem.79, 953 (1967).  相似文献   

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