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1.
Oscar Lopez Lopez 《Tetrahedron》2007,63(36):8872-8880
A series of new α-cyclodextrin derivatives with a substituted propylene bridge attached to the 6-O's of the A,D-glucose units are reported. The compounds were prepared from the known 6A,6D-di-O-(prop-2-methylidene-1,3-dienyl)-hexadeca-O-benzyl-α-cyclodextrin, which was transformed into 6A,6D-di-O-(prop-2-methyl-1,3-dienyl)-α-cyclodextrin, 6A,6D-di-O-(prop-2-formyl-2-hydroxy-1,3-dienyl)-α-cyclodextrin, 6A,6D-di-O-(prop-2-aminomethyl-2-hydroxy-1,3-dienyl)-α-cyclodextrin, 6A,6D-di-O-(prop-2-hydroxymethylidene-1,3-dienyl)-α-cyclodextrin, 6A,6D-di-O-(prop-2-formyl-1,3-dienyl)-α-cyclodextrin, 6A,6D-di-O-(prop-2-carboxy-1,3-dienyl)-α-cyclodextrin and 6A,6D-di-O-(prop-2-methoxycarbonyl-1,3-dienyl)-α-cyclodextrin. The new compounds were evaluated for their ability to affect amine and alcohol oxidations in the presence of hydrogen peroxide.  相似文献   

2.
A Cyclic Methylenediphosphinic Acid: 1,3‐Dihydroxy‐1,3‐dioxo‐1,2,3,4‐tetrahydro‐1λ5,3λ5‐[1,3]diphosphinine Strong acids protonate 1,3‐bis(dimethylamino)‐1λ5,3λ5‐[1,3]diphosphinine ( 5 ) to give the corresponding cation. The protonation is followed by hydrolytic cleavage of the dimethylamino groups resulting in the formation of the cyclic methylenediphosphinic acid ( 6 ).  相似文献   

3.
Starting from Ba2(1,3-pddadp)·8H2O (1,3-pddadp=1,3-propanediamine-N,N′-diacetate-N,N′-di-3-propionate ion) and CoSO4, a new hexadentate [CoII(1,3-pddadp)]2− complex has been prepared. The trans(O6) geometry of this complex was confirmed by comparison of its i.r. and u.v.–vis. spectra with those of [CoII(1,3-pdta)]2− (1,3-pdta is the 1,3-propanediaminetetraacetate ion) and trans(O6)-[CoIII(1,3-pddadp)] complexes of known X-ray crystal structure. Magnetic and electrolytic conductivity properties of these complexes have also been discussed.  相似文献   

4.
The gold(III) 1,3-diaminopropane complex [Au(1,3-pn)(1,3-pn-H)]Cl2 has been synthesized. Its dissociation constant has been determined: Au(1,3-pn)23+ = Au(1,3-pn-H)2+ + H+, logK a1 = −7.03 ± 0.05 (I = 0.1 mol/L NaClO4). Considerable spectral changes are observed for strong alkali solutions (pH 11–14) containing the monoamido forms of the gold(III) ethylenediamine, 1,3-diaminopropane, and diethylenetriamine complexes (Au(en)(en-H)2+, Au(1,3-pn)(1,3-pn-H)2+, Au(dien-H)OH+). These changes are attributed to the formation of the diamido species Au(en-H)2+, Au(1,3-pn-H)2+, and Au(dien-2H)OH0. The dissociation constants of the monoamido complexes have been determined: Au(en)(en-H)2+ (logK a2 = −10.9 ± 0.1 at I = 0.001–0.01 mol/L NaCl); Au(1,3-pn)(1,3-pn-H)2+ (logK a2 = −11.3 ± 0.1 at I = 0.1 mol/L NaCl); Au(dien-H)OH+ (logK a2 = −12.4 ± 0.1 at I = 0.1 mol/L NaCl).  相似文献   

5.
R. Bloch  P. Orvane 《合成通讯》2013,43(11):913-915
2,2-Dialkyl-1,3-indanediones are useful synthetic intermediates (1,2) and are know to possess an anticonvulsive activity (3). These compounds are usually prepared by alkylation of 1,3-indanedione under drastic conditions and thus are obtained with low yields (20% to 40%). We describe here a convenient and high yield procedure for the synthesis of symmetrical and unsymmetrical 2,2-dialkyl-1,3-in-danediones based on alkylation of 1,3-indanediones in the presence of celite coated with potassium fluoride (KF-celite). This new reagent has been very recently used to carry out various alkylation reactions (3). We found that KF-celite promotes excellent C-dialkylation (4) of 1,3-indanedione la, giving rise to symmetrical 2,2-dialkylated compounds 2a. In the same way, unsymmetrical 2,2-dialkyl-1,3 indanediones 2b can be easily prepared from 2-methyl-1,3-indanedione Ib (5).  相似文献   

6.
η5-cyclohexadienyl- and η5-cycloheptadienyl-tricarbonyliron tetrafluoroborate are reduced in refluxing acetonitrile to yield mixtures of 1,3-cyclohexadienetricarbonyliron and 5,5′-di-1,3-cyclohexadienehexacarbonyldiiron, and di-η5-cycloheptadienyltetracarbonyldiiron amd 5,5′-di-1,3-cycloheptadienehexacarbonyldiiron, respectively.  相似文献   

7.
《合成通讯》2013,43(15):2271-2275
A new 1,3-dichlorodisilazane, 1,3-dichloro-1,3-dimethyl-1,3-divinyldisilazane (DMDV), was prepared from the trans-silylation reaction of hexamethyldisilazane (MMN) and methylvinyldichlorosilane. The reactions between MMN and other dichlorosilanes, R2SiCl2 (R = Me, Ph) in the absence of catalyst were also investigated, and the expected, 1,3-dichlorosilazanes, (ClSiMe2)2NH and (ClSiPh2)2NH were obtained, respectively.  相似文献   

8.
The production of 1,3-propanediol (1,3-PD) was investigated with Klebsiella pneumoniae DSM 4799 using raw glycerol without purification obtained from a biodiesel production process. Fed-batch cultures with suspended cells revealed that 1,3-PD production was more effective when utilizing raw glycerol than pure glycerol (productivity after 47 h of fermentation, 0.84 g?L?1?h?1 versus 1.51 g?L?1?h?1 with pure and raw glycerol, respectively). In addition, more than 80 g/L of 1,3-PD was produced using raw glycerol; this is the highest 1,3-PD concentration reported thus far for K. pneumoniae using raw glycerol. Repeated fed-batch fermentation with cell immobilization in a fixed-bed reactor was performed to enhance 1,3-PD production. Production of 1,3-PD increased with the cycle number (1.06 g?L?1?h?1 versus 1.61 g?L?1?h?1 at the first and fourth cycle, respectively) due to successful cell immobilization. During 46 cycles of fed-batch fermentation taking place over 1,460 h, a stable and reproducible 1,3-PD production performance was observed with both pure and raw glycerol. Based on our results, repeated fed batch with immobilized cells is an efficient fermentor configuration, and raw glycerol can be utilized to produce 1,3-PD without inhibitory effects caused by accumulated impurities.  相似文献   

9.
Abstract

Reaction of titanocene prepared from Cp2TiCl2 and 2n-BuLi with β-diketones (β-diketone = 1-phenyl-1,3-butanedione, 1,3-diphenyl-1,3-propanedione, 3-methyl-2,4-pentanedione or 3-ethyl-2,4-pentanedione) afforded the titanocene(III) β-diketonate complex. The compounds [Ti(η5-Cp)2(1-phenyl-1,3-butanedionate)] and [Ti(η5?Cp)2(1,3-diphenyl-1,3-propanedionate)] have been characterized by X-ray crystallography.  相似文献   

10.
In the title coordination polymer, [Ba(1,3‐BDOA)(H2O)2]n (where 1,3‐BDOA2− is the m‐phenylenedioxydiacetate dianion, C10H8O6), each BaII ion is ten‐coordinated by six carboxyl O atoms and two ether O atoms from different 1,3‐BDOA2− ligands, as well as by two water mol­ecules, thus defining a dodeca­hedron. The BaII atoms are covalently linked by 1,3‐BDOA2− ligands in different crystallographic directions, giving rise to a three‐dimensional open framework. The crystal structure is further stabilized by hydrogen bonds and π–π stacking inter­actions. In previously studied polymers of this type, the 1,3‐BDOA2− ligand showed multiple bridging modes with metal ions, including bi‐, tri‐, tetra‐ and hexa­dentate. The title BaII complex represents a novel three‐dimensional coordination polymer constructed by octa­dentate bridging 1,3‐BDOA2− ligands.  相似文献   

11.
The reduction of the (1,3-diformylindenyl)cyclopentadienylruthenium derivatives {η5-1,3-(CHO)2C9H5}RuCp (Cp = C5H5), {η5-1,3-(CHO)2C9H5}RuCp* (Cp* = C5Me5), and {η5-1,3-(CHO)2C9H5}RuCpF (CpF = C5Me4CF3) with NaBH4 or LiAlH4 under mild conditions affords the [1,3-bis(hydroxymethyl)indenyl]cyclopentadienylruthenium complexes {η5-1,3-(CH2OH)2C9H5}RuCp, {η5-1,3-(CH2OH)2C9H5}RuCp*, and {η5-1,3-(CH2OH)2C9H5}-RuCpF, respectively, in good yields.  相似文献   

12.
Three ternary luminescent complexes, Eu (deuterated 1,3-diphenyl-1,3-propanedione)3(1,10-phenanthroline), Eu (deuterated 1,3-diphenyl-1,3-propanedione)3(2,2′-bipyridine), and Eu (deuterated 1,3-diphenyl-1,3-propanedione)3 (bathophenanthroline) were synthesized using bidental oxygen and nitrogen as ligands. Luminescent polymers were fabricated by incorporating deuterated Eu(III) complexes in a poly(methyl methacrylate) matrix. Luminescent poly(methyl methacrylate) containing Eu (deuterated 1,3-diphenyl-1,3-propanedione)3 (bathophenanthroline) exhibited relatively higher quantum yield, faster radiation rate, sharper red emission and larger stimulated emission cross-section (quantum yield 36%, radiation rate 8.6 × 102 s?1, full width at half maximum 3.4 nm, and stimulated emission cross-section σ p = 1.4 × 10?20 cm2) of the PMMA matrix. The value of σ p was the same order as the values of Nd-glass laser for practical use. Additionally, the thermal behaviors of the Eu(III) ternary complexes were studied, and the results indicated that all of them can be long-term used in high temperature environment. Prepared luminescent polymer including Eu (deuterated 1,3-diphenyl-1,3-propanedione)3 (bathophenanthroline) showed promising results for applications in novel organic Eu(III) devices, such as high-power laser materials and optical fibers.  相似文献   

13.
By reaction of [Ir(COD)Cl]2 (COD = 1,5-cyclooctadiene) with i-C3H7MgBr in the presence of cyclic dienes, complexes of the type [IrH(COD)L] (L = 1,3-cyclohexadiene, 2-methyl-],3-cyclohexadiene, 5-ethyl-1,3-cyclohexadiene, 1,3-cycloheptadiene) are obtained. The system IrCl3/i-C3H7MgBr/1,3-C6H8 yields [IrH(1,3-C6H8)2]. According to NMR spectroscopic investigations the pure hydrido forms exist in solution only at low temperatures while at room temperature dynamic H-addition—elimination equilibria of the type [IrH(η4-diene)(COD)] ? [Ir(η3-enyl)(COD)] and [IrH(η4-1,3-C6H8)2] ? [Ir(η3-C6H9)-(η4-1,3-C6H8)], respectively, are observed; the hydrogen at the iridium atom is thereby transferred to the endo positions of the diene ligands.  相似文献   

14.
Abstract

The 1H, 13C and 77Se NMR chemical shifts for 1,3-dithiolium, 1,3-thiaselenolium and 1,3-diselenolium tetrafluoroborates which are unsubstituted in the 4 and 5 positions and are unsubstituted or contain ethylseleno, ethylthio or morpholino groups in the 2 positions are reported. The dependence of the chemical shifts on the substituents and ring hetero atoms are discussed and shift increments given. The study includes the 13C shift effects for the following series of compounds: (a) thiotropone, ethylthiotropylium cation and tropylium cation; the iso-π-electronic heterocycles (b) thiopyrane-2-thione, 2-ethyl-thiothiopyrylium cation and the thiopyrylium cation, (c) 1,2-dithiole-3-thione, 3-ethylthio-1,2-dithiolium cation and the 1,2-dithiolium cation, and (d) 1,3-dithiole-2-thione, 2-ethylthio-1,3-dithiolium cation and the 1,3-dithiolium cation. Linear correlations between δ (1H) and δ (13C), δ (77Se) and δ (13C) and δ (13C) and δ (13C) (i) of neighbouring ring positions and (ii) between ring and substituent atoms proves, that changes in the electron density distribution of the ring systems is the intrinsic reason for the shift effects discussed. In particular the 77Se/13C shift correlations show, that δ (77Se) of double coordinated selenium atoms is determined by the 〈r ?34p term in the contribution of paramagnetic screening σp(77Se).

Es werden die 1H-,13C- und 77Se-NMR-chemischen Verschiebungen der in 4/5-Position unsubstituierten 1,3-Dithiolium-, 1,3-Thiaselenolium- und 1,3-Diselenolium-tetrafluoroborate, die in 2-Stellung unsubstituiert sind bzw. den Ethylseleno-, Ethylthio- oder Morpholinrest tragen, mitgeteilt und in Abhängigkeit von den Substituenten und den Ring-Heteroatomen diskutiert.

In die Betrachtung einbezogen sind die 13C-Verschiebungseffekte beim Übergang von den Thionen über die SEt-substituierten Kationen zu den Kation-Grundverbindungen in der Reihe Thiotropon/Ethyl-thiotropyliumion/Tropyliumion und der jeweiligen iso-π-elektronischen Schwefelheterocyclen Thiopyran-2-thion/2-Ethylthiothiopyryliumion/Thiopyryliumion, 1,2-Dithiol-3-thion/3-Ethylthio-1,2-dithioliumion/1,2-Dithioliumion und 1,3-Dithiol-2-thion/2-Ethylthio-1,3-dithioliumion/1,3-Dithioliumion.

Aufgefundene lineare Korrelationen zwischen δ (1H) und δ (13C), δ (77Se) und δ (13C) sowie δ (13C) und δ (13C) sowohl benachbarter Ringpositionen als auch zwischen Ring- und Substituentenatomen beweisen, daß als Ursache der diskutierten Verschiebungseffekte im Wesentlichen Änderungen der Elektronendichteverteilung der Ringsysteme anzusehen sind. Speziell die 77Se/13C-Verschiebungskorrelationen zeigen, daß für δ (77Se) zweifach koordinierter Selenatome der 〈r ?34p-Term im σp (77Se)-Verschiebungsbeitrag entscheidend ist.  相似文献   

15.
This paper reports the 77Se NMR chemical shifts of 1,3-dithiole-, 1,3-thiaselenole- and 1,3-diselenole-2-ones, -thiones and -selones, of the corresponding saturated compounds 1,3-diselenolane-2-one, -thione and -selone, and the 1,3-thiaselenolium tetrafluoroborates, either unsubstituted or substituted by morpholino, ethylthio or ethylseleno groups in the 2-position. The 77Se chemical shift values of the ring selenium and the C?Se groups are compared with the 13C chemical shift values of neighbouring carbon atoms. The relationships between the 77Se chemical shifts of the C?Se groups and the wavelengths of their n→* absorption in the UV-visible spectrum are discussed with respect to the significance of the δE term in the contribution of the paramagnetic screening and the electron density distribution.  相似文献   

16.
Summary AM1 semi-empirical SCF MO calculations are reported for important conformations of oxocane (1) and 1,3-dioxocane (2). The boat-chair conformation of1 (BC-1) is found to be the most stable form, whereas the crown family conformation is calculated to be 3.7 kJ·mol–1 less stable. The boat-boat form of1 is 15.9 kJ·mol–1 less stable thanBC-1. The boat-chair conformation of2 (BC-1,3) is calculated to be the most stable form of 1,3-Dioxocane. The crown-family conformation and the boat-boat geometry of this compound are 4.2 and 8.3 kJ mol–1 less stable thanBC-1,3.
AM1-Rechnungen zu den Konformationen von Oxocane und 1,3-Dioxocan
Zusammenfassung Die wesentlichen Konformationen von Oxocan (1) und 1,3-Dioxocan (2) wurden mittels semiempirischer AM1-Rechnungen (SCF MO) untersucht. Die Wanne-Sessel-Konformation von1 (BC-1) ist am stabilsten; Konformationen aus der Klasse der Kronen sind um 3.7 kJ·mol–1 energiereicher. Die Wanne-Wanne-Konformation von1 ist um 15.9 kJ·mol–1 instabiler alsBC-1. Die Wanne-Sessel-Konformation von2 (BC-1,3) ist das stabilste Konformer von 1,3-Dioxocan. Kronenkonformationen und Wanne-Wanne-Geometrien sind um 4.2 und 8.3 kJ·mol–1 energiereicher alsBC-1,3.
  相似文献   

17.
1,3-bis(Dimethylhydroxysilyl)adamantane(I) has been prepared. Thermal condensation polymerization of this monomer yields poly-1,3-adamantyl-1,1,3,3-tetramethyldisiloxane. Condensation of I with bis(dimethylamino)dimethylsilane or 1,3-bis(dimethylamino)-1,1,3,3-tetramethyldisiloxane gave the expected 1,3-adamantyl dimethylsiloxane copolymers (II and III) respectively. These polymers have been characterized by 1H,13C, and 29SiNMR as well as GPC and TGA. They have unusually high thermal stability.  相似文献   

18.
The correlation between the intensities of the M and [M ? H]+ ions of 47 cyclic acetals and thioacetals of alkyl formylphenoxyacetates and propionates as well as the fragmentation patterns in the vicinity of the molecular ion are discussed. The characteristic differences between the spectra of 1,3-dioxolanes, 1,3-oxathiolanes, 1,3-dithiolanes and 1,3-dioxanes are presented.  相似文献   

19.
《Thermochimica Acta》1987,122(1):189-195
The sublimation enthalpies of monophenylurea (MPhU) and diphenyl-1,3 urea (1,3-DPhU) have been derived from the dependence of their vapour pressures on temperature, as measured by the torsion-effusion method. Values obtained are: 136 kj mol−1 for MPhU and 152 kJ mol−1 for 1,3-DPhU, where the estimated errors are comprised within 6 kJ mol−1Enthalpies and temperatures of fusion have been measured by differential scanning calorimetry, leading to 23.7 kJ mol−1 and 420.6 K for MPhU, and 34.6 kJ mol−1 and 512 K for 1,3-DPhU. Poor reproducibility of results for 1,3-DPhU seems be due to the beginning of decomposition. No solid-to-solid transitions have been revealed from r.t. to fusion for both compounds.  相似文献   

20.
Relativistic corrections to order (υ/c)2 are applied to the helium excited states 2 1,3P, 3 1,3D,…, 8 1,3K. Simple correlated open-shell wavefunctions are employed and the Breit operators H1 through H5 treated as perturbations. Account is also taken of mass polarization and lowest-order one electron Lamb shift. The energies thus calculated agree with experiment to within 2.2 cm?1 or better.  相似文献   

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