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1.
Synthesis of difunctional N,N′-difluoro perfluoroalkylsulfonamides, CF3SO2NFSO2(CF2)nSO2NFSO2CF3, where n=4, 6 is reported. A related compound with an oxygen linkage CF3SO2NFSO2(CF2)2O(CF2)2SO2NFSO2CF3 has also been prepared. These reagents showed good activity for electrophilic fluorination.  相似文献   

2.
A new alternative system for the chemoselective oxidation of secondary hydroxyl group to ketone with IBX/n-Bu4NBr in CH2Cl2-H2O has been developed. Under the reaction conditions, the secondary hydroxyl group was highly chemoselectively oxidized to the corresponding ketone, in moderate to good yields at rt, in the presence of primary hydroxyl group within the same molecule.  相似文献   

3.
4.
The crystal structure of the ternary intermetallic compound Yb3Pd2Sn2 has been determined ab initio from powder X-ray diffraction data. The compound crystallizes as a new structure type in the orthorhombic space group Pbcm and lattice constants a=0.58262(3), b=1.68393(8), c=1.38735(7) nm. Yb3Pd2Sn2 is composed of a complex [Pd2Sn2]δ− polyanionic network in which the Yb ions are embedded. A comparison between this structure and those of Eu3Pd2Sn2 and Ca3Pd2Sn2, other novel polar intermetallic compounds, was made. DC susceptibility and 170Yb Mössbauer spectroscopic measurements indicate a close-to divalent Yb behavior. Moreover, a hybridization between 4f and conduction electrons is suggested by electronic structure calculations and heat capacity measurements.  相似文献   

5.
A new procedure for the deprotection of carboxylic tert-butyl and 1-adamantyl esters, and N-Boc-amines using H2SO4 in CH2Cl2 is described. The proposed method is simple, cheap, eco-friendly and represents a valid alternative to existing ones, with special significance in large scale applications.  相似文献   

6.
The hydrated potassium hemimagnesium dihydrogen pyrophosphate KMg0.5H2P2O7·H2O was synthesized. It crystallizes in the triclinic system, space group (n. 2), Z=2, with the following unit-cell parameters: a=6.8565(2) Å, b=7.3621(3) Å, c=7.6202(3) Å, α=81.044(2)°, β=72.248(2)°, γ=83.314(3)°, V=360.90(2) Å3. The structure was obtained by single-crystal X-ray diffractometry, and a full-matrix least-squares refinement based on F2 gave a final R index of =0.0368 (wR=0.0975), utilizing 1446 observed reflections with I>2σ(I). The crystal packing consists in a three-dimensional network made by layers parallel to ab plane of PO4 double tetrahedra and MgO6 octahedra, linked by hydrogen bonds, while K atoms form complex coordination within cavities between tetrahedra and octahedra. The dihydro-pyrophosphate anion (H2P2O7)2− shows bent eclipsed conformation and the Mg2+ ion lies on inversion center. No coincidences observed between most of infrared and Raman spectral bands confirmed the centrosymmetric structure of the title compound; the vibrational spectra point to a bent POP bridge angle.  相似文献   

7.
An efficient, simple protocol for the selective cleavage of a variety of N-alkoxycarbonyl protecting groups by t-BuNH2/MeOH is described. The scope of the procedure was explored for a series of indole, aniline and pyrrolidine carbamate derivatives containing other potentially reactive functional groups affording a clean cleavage of the carbamate group.  相似文献   

8.
A dinuclear copper(Ⅱ) complex[Cu2(TATP)2(L-Leu)2(CIO4)2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the triclinic space group P1, with two independent molecules in a unit cell. Two Cu(Ⅱ) ions in each complex [Cu2(TATP)2(L-Leu)2(CIO4)2] molecule were found to be in different coordination geometries, i.e., Cu2 or Cu4 of a distorted square-pyramidal geometry coordinated with two nitrogens of TATP, the amino nitrogen and one carboxylate oxygen of L-Leu and one oxygen of perchlorate, and Cul or Cu3 with an octahedral geometry coordinated with the above stated similar coordinated atoms, and another carboxylate oxygen of L-Leu coordinating to Cu2 or Cu4. The complex can interact with CT-DNA by an intercalative mode and cleave pBR322 DNA in the presence of ascorbate.  相似文献   

9.
Single crystals of the new compounds TM2Cu3Ga8 (TM=V, Mo, W) were synthesised from the elements. Structure determinations of the isotypic compounds (cI104, space group , Z=8; Mo2Cu3Ga8: a=11.9171(10) Å, 613 refl., 23 param., R1(F)=0.022, wR2(F2)=0.047; W2Cu3Ga8: 11.9248(8) Å, 346 refl., 23 param., R1(F)=0.048, wR2(F2)=0.086; V2Cu3Ga8: 11.7861(14) Å, 374 refl., 24 param., R1(F)=0.033, wR2(F2)=0.081) showed a new cubic structure type which can be classified as an ordered defect variant of a bcc packing with a=4a: [(TM)2(Cu)3(□)3][Ga8]. The coordination polyhedra of the transition metals consist of Ga8-cubes with 3 sides capped by Cu leading to coordination number 11. The arrangement of the TMGa8Cu3-polyhedra is in a way they form itself a 3-fold capped cube. All compositions were confirmed by EDX measurements.  相似文献   

10.
The reaction of lanthanide nitrate with 1,4-di (N,N-diisopropylacetamido)-2,3(1H,4H)-quinoxalinedione (L) yields six novel Ln(III) complexes ([Ln2L2(NO3)6(H2O)2]·H2O) which are characterized by elemental analysis, thermogravimetric analysis (TGA), conductivity measurements, IR, electronic and 1H NMR spectroscopies. A new quinoxalinedione-based ligand is used as antenna ligand to sensitize the emission of lanthanide cations. The lowest triplet state energy level of the ligand in the nitrate complex matches better to the resonance level of Eu(III) and Sm(III) than Tb(III) and Dy(III) ion. The f-f fluorescence is induced in the Eu3+ and Sm3+ complexes by exciting into the π-π* absorptions of the ligand in the UV. Furthermore, the crystal structures of a novel binuclear complex [Nd2L2(NO3)6(H2O)2]·H2O has been determined by single-crystal X-ray diffraction. The binuclear [Nd2L2(NO3)6(H2O)2]·H2O complex units are linked by the intermolecular hydrogen bonds and π-π interactions to form a two-dimensional (2-D) layer supramolecule.  相似文献   

11.
A Pd2dba3/P(i-BuNCH2CH2)3N catalyzed one-pot synthesis of unsymmetrically substituted trans-4-N,N-diarylaminostilbenes and both symmetrically and unsymmetrically substituted N,N-diarylaminostyrene derivatives is reported. The procedure involves two or more palladium catalyzed sequential coupling reactions (an amination and an inter-molecular Heck reaction) in one-pot using the same catalyst system with two different aryl halides, including aryl chlorides and hetero aryl halides as the coupling partners.  相似文献   

12.
New bimetallic complex [Cp2ZrH2 · ClAlEt2]2 (1) was synthesized, and its reactivity in hydrometallation reaction with the following alkenes was studied: hept-1-ene, okt-1-ene, α-methylstyrene, (1S)-β-pinene, (+)-camphene. Complex 1 shows the highest reactivity among the other known Al,Zr-bimetallic complexes: [Cp2ZrH2 · ClAlBui2]2 (2), [Cp2ZrH2 · AlEt3]2 (3), [Cp2ZrH2 · AlBui3]2 (4) and [Cp2ZrH2 · HAlBui2] (5) as well as organoaluminium compounds (OAC): iBu2AlH, iBu3Al and iBu2AlCl in presence of Zr catalysts. Chlorine containing complexes 1 and 2 appear to be more effective in alkene hydrometallation, and relative hydrometallation rates are (1S)-β-pinene ? (+)-camphene < α-methylstyrene < oct-1-ene < hept-1-ene. Hydrometallation of (1S)-β-pinene and its subsequent oxidation with I2 run with high diastereoselectivity and yield trans-myrtanol. However, the diastereoselectivity of (+)-camphene hydrometallation is less than that for (1S)-β-pinene, and the reaction gives predominately endo-camphanol.  相似文献   

13.
Three new compounds Ca(HF2)2, Ba4F4(HF2)(PF6)3 and Pb2F2(HF2)(PF6) were obtained in the system metal(II) fluoride and anhydrous HF (aHF) acidified with excessive PF5. The obtained polymeric solids are slightly soluble in aHF and they crystallize out of their aHF solutions. Ca(HF2)2 was prepared by simply dissolving CaF2 in a neutral aHF. It represents the second known compound with homoleptic HF environment of the central atom besides Ba(H3F4)2. The compounds Ba4F4(HF2)(PF6)3 and Pb2F2(HF2)(PF6) represent two additional examples of the formation of a polymeric zigzag ladder or ribbon composed of metal cation and fluoride anion (MF+)n besides PbF(AsF6), the first isolated compound with such zigzag ladder. The obtained new compounds were characterized by X-ray single crystal diffraction method and partly by Raman spectroscopy. Ba4F4(HF2)(PF6)3 crystallizes in a triclinic space group P1¯ with a=4.5870(2) Å, b=8.8327(3) Å, c=11.2489(3) Å, α=67.758(9)°, β=84.722(12), γ=78.283(12)°, V=413.00(3) Å3 at 200 K, Z=1 and R=0.0588. Pb2F2(HF2)(PF6) at 200 K: space group P1¯, a=4.5722(19) Å, b=4.763(2) Å, c=8.818(4) Å, α=86.967(10)°, β=76.774(10)°, γ=83.230(12)°, V=185.55(14) Å3, Z=1 and R=0.0937. Pb2F2(HF2)(PF6) at 293 K: space group P1¯, a=4.586(2) Å, b=4.781(3) Å, c=8.831(5) Å, α=87.106(13)°, β=76.830(13)°, γ=83.531(11)°, V=187.27(18) Å3, Z=1 and R=0.072. Ca(HF2)2 crystallizes in an orthorhombic Fddd space group with a=5.5709(6) Å, b=10.1111(9) Å, c=10.5945(10) Å, V=596.77(10) Å3 at 200 K, Z=8 and R=0.028.  相似文献   

14.
Using tris(2-aminoethyl)amine [(C2H4NH2)3N] (tren) as a template, two new tantalum fluorides are obtained by slow evaporation of solutions: [H4tren](TaF7)2·H2O (I) and [H4tren](TaF7)2 (II). The structure determinations are performed by single crystal X-ray technique. Structures of I and II are built up from isolated TaF7 distorted monocapped trigonal prisms or pentagonal bipyramids; charge balance is achieved by tetraprotonated [H4tren]4+ cations which possess a “scorpion” configuration. In I and II, TaF7 polyhedra, connected by hydrogen bonds with water molecules in I, lie in corrugated layers; hydrogen bond networks ensure the cohesion between these layers and [H4tren]4+cations.  相似文献   

15.
The ternary intermetallic compounds RE2Cu2Cd (RE=Y, Sm, Gd-Tm, Lu) were synthesized by induction-melting of the elements in sealed tantalum tubes. The samples were characterized by X-ray powder diffraction. The structure of Gd2Cu2Cd was refined from single crystal X-ray diffractometer data: Mo2FeB2 type, space group P4/mbm, a=756.2(3), c=380.2(3) pm, wR2=0.0455, 321 F2 values, 12 variables. The structures are 1:1 intergrowth variants of slightly distorted CsCl and AlB2 related slabs of compositions RECd and RECu2. The copper and cadmium atoms build up two-dimensional [Cu2Cd] networks (257 pm Cu-Cu and 301 pm Cu-Cd in Gd2Cu2Cd) which are bonded to the rare earth atoms via short RE-Cu contacts (290 pm in Gd2Cu2Cd). Temperature dependent susceptibility measurements of RE2Cu2Cd with RE=Gd, Tb, Dy, and Tm show experimental magnetic moments which are close to the free RE3+ ion values. The four compounds show ferromagnetic ordering at TC=116.7(2), 86.2(3), 48.4(1), and 14.5(1) K, respectively, as confirmed by heat capacity measurements. Dy2Cu2Cd shows a spin reorientation at TN=16.9(1) K.  相似文献   

16.
The first organically templated 3d-4f mixed metal sulfates, [H2en]2{La2M(SO4)6(H2O)2} (M=Co 1, Ni 2) have been synthesized and structurally determined from non-merohedrally twinned crystals. The two compounds are isostructural and their structures feature a three-dimensional anionic network formed by the lanthanum(III) and nickel(II) ions bridged by sulfate anions. The La(III) ions in both compounds are 10-coordinated by four sulfate anions in bidentate chelating fashion, and two sulfate anions in a unidentate fashion. The transition metal(II) ion is octahedrally coordinated by six oxygens from four sulfate anions and two aqua ligands. The doubly protonated enthylenediamine cations are located at the tunnels formed by 8-membered rings (four La and four sulfate anions).  相似文献   

17.
18.
Platinum(II) and palladium(II) complexes containing chelating acyl ligands have been synthesized from salicylaldehyde, 2-hydroxynaphthaldehyde and 2-hydroxy-3-methoxybenzaldehyde. The platinum(II) complexes [Pt(acyl)L2], acyl  OC6H4CO, OC10H6CO, O(m-CH3OC6H3CO), L  tertiary phosphine, 1/2 diphenylphosphinoethane, can be isolated with both monodentate and chelating diphosphines, whereas for palladium only the compounds with chelating phosphines are readily obtainable. The reactions of [Pt(OC6H4CO)L2] with HCl afford trans-[PtCl(OHC6H4CO)L2], L  monodentate tertiary phosphine and cis-[PtCl(OHC6H4CO)L2], L2  1,2-bis-diphenylphosphinoethane, in which the metal—carbon bond remains intact. The structure of [Pt(OC6H4CO)-(P(p-CH3C6H4)3)2] has been determined by X-ray diffraction methods and found to have the expected square planar structure. Some relevant bond lengths and angles are: PtP; 2.271(4) and 2.348(5) Å; PtC; 1.96(2) Å and PtO; 2.07(1) Å; PPtP  101°, CPtO  82°.  相似文献   

19.
A series of meso-furyl porphyrins with four different porphyrin cores (N4, N3S, N2S2 and N3O) were synthesized and characterized. The comparison of NMR, optical and fluorescence properties of meso-furyl porphyrins with porphyrins with six-membered aryl groups indicates that electronic properties of porphyrins were changed drastically on the introduction of furyl groups at meso positions. The maximum shifts in spectral bands were observed for meso-furyl porphyrins with N2S2 core. On protonation, the absorption bands of meso-furyl porphyrins were further red shifted. All these changes were ascribed to the possibility of more planarity of the meso-furyl porphyrins due to the small size of the furyl groups which results in extending the π-delocalisation of the porphyrin ring in to the furyl groups.  相似文献   

20.
Intercalation behavior of n-alkylamines into a protonated form of an A-site defective layered perovskite H2W2O7 has been investigated. Results from XRD indicate these materials are layered with the corresponding interlayer spacing governed by the n-alkylamine chain length, and a reversible intercalation and deintercalation property is observed among these intercalation compounds. The IR spectra of the intercalation compounds with n-alkylamines clearly show that n-alkyl chains possess an all-trans conformation, and H2W2O7 accommodate n-alkylamines (CnH2n+1NH2: n=3, 4, 7, 8, 12, 16) to form intercalation compounds via an acid-base mechanism. A linear relationship between the interlayer distance and the number of carbon atoms in n-alkyl chains is observed to show a bilayer arrangement of the n-alkyl chains with a tilt angle of ∼71.6°. Elemental analysis studies reveal that the amounts of intercalated n-alkylamines are about 2.0 mol per [W2O7]. Despite the surface geometry of H2W2O7 is almost identical to those of layered perovskites H2[An−1BnO3n+1], the amounts of intercalated n-alkylamines of them are different. A reasonable explanation is given through our research.  相似文献   

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