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1.
The condensation of 2-anilinoacetophenone with RFCO2Et (RF = CF2H, CF3, C2F5) in the presence of LiH in THF affords the corresponding N-phenyl-2-polyfluoroalkyl-4-quinolones in excellent yields.  相似文献   

2.
Kinetic analysis of the free radical addition of n-C6F13I to 1,6-heptadiene gives a rate ratio of cyclization to addition (kd1/kc) of 0.568 at 70 °C; thus, the rate of cyclization (kc) is twice that of iodine transfer (kd1). By contrast, for n-C6F13CH2CH2SH (kd1/kc) = 14.4 at 70 °C, and radical transfer of H from the thiol is 14.4 times the faster than cyclization. Substitution at the center of 1,6-heptadiene has a profound effect on the linear/cyclic adduct ratio. For the addition of n-C3F7I (RFI:diene=2:0) the adduct ratios dramatically decrease in the order: 1,6-heptadiene (1.17) > 4-carboxy-1,6-heptadiene (0.0613) > 4,4-bis-ethoxycarbonyl-1,6-heptadiene (<0.001). Bis-addition to the 4,4-substituted dienes is strongly disfavored, and the desired “geminal-twin-tail” [RF(CH2)3]2CHCO2R, or [RF(CH2)3]2C(CO2R)2 must be synthesized by other means. For the reaction of RFCH2CH2SH with the dienes (1:1), the respective adduct ratios are 11.3 (n-C6F13), 0.370 (n-C8F17), and 0.0716 (n-C6F13). However, adding the 4-carboxy-1,6-heptadiene slowly to four mols of n-C8F17CH2CH2SH yields 98% of the geminal bis-adduct [RFCH2CH2S(CH2)3]2CHCO2H, which is a new, fluorophilic, geminal-twin-tail acid.  相似文献   

3.
Synthesis and Properties of Tetrakis(Perfluoroalkyl)Tellurium Te(Rf)4 (Rf = CF3, C2F5, C3F7, C4F9) Te(CF3)4 is obtained from the reaction of Te(CF3)Cl2 with Cd(CF3)2 complexes as a complex with e. g. CH3CN, DMF. It is a light and temperature sensitive hydrolysable liquid. The reaction with fluorides yields the complex anion [Te(CF3)4F]?, with fluoride ion acceptors the complex cation [Te(CF3)3]+. With traces of water an acidic solution is formed. Te(CF3)4 acts as a trifluoromethylation reagent. The reaction with XeF2 gives hints for the formation of Ye(CF3)4F2. Properties and NMR spectra are discussed. The much more stable complexes of Te(Rf)4 (Rf = C2F5, C3F7, C4F9) are formed from the reaction of TeCl4 with the corresponding Cd(Rf)2 complexes.  相似文献   

4.
Study of solid-liquid phase diagram of LiPO3-Pb(PO3)2 binary system, in certain calcination conditions, shows the existence of several metastable phasis. When heated at a temperature of 723 K the binary mixtures lead uncompletely to a defined compound Pb2Li(PO3). On heating these ternary solid mixtures, three eutectic reactions have been observed: LiPO3+Pb(PO3)2→Liquid at a temperature of 793 K(1) LiPO3+Pb2Li(PO3)5→Liquid at a temperature of 843 K (2) Pb2Li(PO3)5+Pb(PO3)2→Liquid at a temperature of 891 K (3) The metastable liquid phase appears in the system at temperature of 793 K. DTA experiments performed on the binary LiPO3-Pb(PO3)2 mixtures, show a superposition of two diagrams. The first one is metastable and the second represents the stable equilibrium phase diagram. Measurements of liquid enthalpy of binary LiPO3-Pb(PO3)2 system at temperature of 979.65 K were reported. The corresponding values were very small and so the binary system can be considered as athermal. Assuming an ideal behaviour, the liquidus curves in the metastable diagram were calculated and the eutectic reaction (LiPO3-Pb(PO3)2→Liquid) was confirmed at 793 K. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

5.
《Solid State Sciences》1999,1(4):233-243
Diamido-difluoro-tin Sn(ND2)2F2 can be produced by ammonolysis from (NH4)2SnF6 at 633 K. The compound is a product formed from Sn(ND3)2F4 during the ammonolysis reaction. Sn(ND2)2F2 isostructural with Sn(NH2)2F2 crystallizes in space group C2/m with lattice constants a = 1072.92(7), b = 325.97(1) pm, c = 505.79(4) pm and β = 105.713(6) ° (V = 170.28(1) ·106 pm3) containing two formula units per unit cell. Data refinement by the Rietveld method of neutron time-of-flight data collected at POLARIS yields a weighted profile R-value Rwp = 0.022. Tin is octahedrally coordinated by two fluorine atoms and four amido groups. The octahedra are connected to one-dimensional chains by edge sharing. The ND2 groups are in the bridging position whilst the fluorine atoms are terminal. Nearly linear (175.2(4) °) and angular (134.35(8) °) N-D···F hydrogen linkages connect the chains.  相似文献   

6.
Perfluoroalkyl- or nonafluoro-tert-butoxy-alkyl-substituted enantiopure amines having the structure PhCHCH3(NR1R2) [R1 = H, CH3; R2 = (CH2)3C8F17, (CH2)2OC(CF3)3; R1 = R2 = (CH2)3C8F17, (CH2)2OC(CF3)3] are obtained in high yields, when (S)-(−)-1-phenylethylamine is reacted with readily accessible alkylating reagents or fluorous 2° amines (R1 = H; R2 = (CH2)3C8F17, (CH2)2OC(CF3)3) are methylated in a Leuckart-Wallach reaction. The solubility patterns of these novel chiral amines and their hydrochlorides are qualitatively described for a broad spectrum of solvents and the fluorous partition coefficients of the free bases are determined by GC. A novel method for the resolution of enantiomers is disclosed here, which involves the use a half-equivalent of the selected resolving agent in solvent water that displays low solubility for the crystalline diastereomeric salt(s) formed even at temperatures near to its boiling point. Compound (S)-(−)-PhCHCH3[NH(CH2)3C8F17] is found to satisfy all the latter conditions and successfully used for the heat facilitated resolution of the title racemic acid. The circular dichroism (CD) spectra of six novel fluorous (S)-(−)-1-phenylethylamine derivatives are measured in ethanol, trifluoroethanol and hexafluoropropan-2-ol and discussed in detail.  相似文献   

7.
The preparations, stabilities and structures of the complexes R2TlX and R2 LTlX (R = C6F5, p-HC6F4, or o-HC6F4; X = Br or Cl; L = Ph3PO, 2,2′-bipyridyl (bpy) or Ph3P) have been examined or (R = C6 F5) reinvestigated. The derivatives R2TlX are monomeric in acetone, from which the complex (p-HC6F4)2 Me2COTIBr has been isolated. In this solvent, the complexes R2LTlX (L = Ph3PO, bpy, or Ph3P) undergo partial dissociation by loss of L. When L = bpy, there is also slight ionization into R2LTl+ and R2TlX?2. The acceptor properties of R2TlX compounds towards uncharged ligands decrease R = C6F5 ? p-HC6F4 > o-HC6F4 > Ph. Dimeric behaviour is observed for R2TIX compounds in benzene, whilst R2LTlX (L = Ph3PO or bpy) derivatives show slight but significant association. In the solid state, R2TlX compounds are considered to be polymeric with five coordinate thallium, and R2LTlX derivatives to be dimeric with five (L = Ph3PO) or six (L = bpy) coordinate thallium by contrast with four coordinate dimeric and four or five coordinate monomeric structures previously proposed for the respective pentafluorophenyl derivatives. Halogen bridging is unsymmetrical for R = C6F5 or p-HC6F4, but may be more symmetrical for R = o-HC6F4 when L = Ph3PO or bpy. Reported structural data for the complexes (C6F5)LTlX (L = Ph3AsO, Ph3P, Ph3As, or 1,10-phenanthroline; X = Br or Cl) and (C6F5)2TlCl?2 are reinterpreted and the proposed structures revised.  相似文献   

8.
Perfluoroalkanesulfonic anhydrides (RFSO2)2O when mixed with acids decompose into perfluoroalkanesulfonic esters RFSO2ORF, thereby providing a new facile synthesis of these esters from perfluoroalkanesulfonic acids and phosphorus pentoxide.  相似文献   

9.
Kinetics of fluorideion exchange at the interface between a LaF3:Eu2+ single crystal and solution with different pF and pH is studied by the galvanostatic and potentiometric methods and also by impedance spectroscopy. Anodic galvanostatic transients are linearized in the coordinates ln (η–ηmax) vs. t, which suggests that the exchange rate in alkaline solutions is limited by surface diffusion of fluorine adions. The surface concentration of fluorine adions с 0 and the surface diffusion flow ν 0 are assessed. Impedance spectroscopy studies of the exchange processes indicate that the charge-transfer resistance R F and the heterogeneous reaction resistance R P increase with the increase in the рН of the fluoride-containing solution and also with the increase in the time of exposure of the fluoride-selective electrode membrane in a neutral solution with pH 6.4 and the high (pF 2) content of fluorides.  相似文献   

10.
We have studied on the solubilization of single-walled carbon nanotubes (SW-CNTs) into aqueous and organic media by the use of a variety of nanometer size-controlled fluorinated self-assemblies, which were formed by the aggregations of end-capped fluoroalkyl segments in fluoroalkyl end-capped acrylic acid oligomers [RF-(ACA)n-RF], N,N-dimethylacrylamide oligomers [RF-(DMAA)n-RF], acryloylmorpholine oligomers [RF-(ACMO)n-RF], and N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomers [RF-(DOBAA)n-RF]. Fluorinated self assemblies formed in organic media (colorless solutions) could solubilize SW-CNTs into organic media to afford the transparent pale yellow solutions. The dynamic light scattering measurements showed that the size of fluorinated self-assemblies increased after the solubilization of SW-CNTs into organic media. It was suggested that the solubilization of SW-CNTs into organic media is due to the encapsulation of SW-CNTs into fluorinated assemblies. Fluorinated assemblies were also able to solubilize SW-CNTs into water to give the transparent gray solutions. Among a variety of fluorinated assemblies, fluorinated assemblies formed by RF-(ACMO)n-RF [RF = CF(CF3)OC6F13] oligomer was more effective for the solubilization of SW-CNTs into both aqueous and organic media. Contact angle measurements of dodecane and the fluorescence spectra for poly(methyl methacrylate) cast film modified by fluorinated self-assemblies—SW-CNTs complexes showed that SW-CNTs are dispersed above the PMMA surface.  相似文献   

11.
The structure of π-C5H5Fe(CO)[(CHNCH3)2BH2] has been determined from three dimensional X-ray diffractometer data collected by counter methods. The compound crystallizes in the space group P21/a with four molecules in a cell of dimensions a = 12.33(3), b = 6.14(2) and c = 16.21(7)Å with β = 105.0(2)°. The observed and calculated densities are 1.37(2) and 1.379(6) g/cm3 respectively. Full-matrix least-squares refinement has resulted in R = 0.113 for the 1238 data with F2o ? σ (F2o). The structure results from a BH?4 anion adding across two coordinated isocyanide ligands to form a six-membered heterocyclic ring containing BN bonds.  相似文献   

12.
The hydrothermal synthesis and the structure determination from powder or single crystals X-ray diffraction of 3 new metallophosphonates are presented. Crystal data: Ga(OH)0.28F0.72PO3(CH3): P21/c (n∘ 14), a = 7.7912(7) Å, b = 7.2310(6) Å, c = 9.3114(8) Å, β = 106.873(2) °, V = 502.00(8) Å 3, Z = 4, R1(F) = 0.0409, wR2(F2) = 0.0933 for 1 266 reflections I > 2 σ (I) with 77 parameters. Ga3(OH)3F3(MePO3)2 H2N(CH2)3NH3: P-3 (No. 147), a = b = 7.2514(2) Å, c = 7.9413(2) Å, V = 361.6(3) Å3, Z = 6, RF = 7.95, RBragg = 7.18, Rwp = 17.3, Rp = 12.0. (VIVO(H2O))(CuII(H2O))O3P-CH2-PO3: P212121 (No. 19), a = 6.3884(3) Å, b = 10.7284(4) Å, c = 11.2762(5) Å, V = 772.84(6) Å3, Z = 4, R1(F) = 0.0395, wR2(F2) = 0.0861 for 2 012 reflections I > 2 σ (I) and 128 parameters.  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.
Sodium dithionite-initiated addition of RFI (1) [RF=1a, Cl(CF2)4; 1b, Cl(CF2)6; 1c, Cl(CF2)6; 1d, n-C6F13; 1e, n-C3F17] to the properly protected glucose derivatives 2, 9, 12 and 15 gave polyfluoroalkylated glucose derivatives 7, 11, 14 and 17 respectively in good yields after reduction and deprotection. These compounds are strongly surface active.  相似文献   

15.
The X-ray structure determination of [NH2)2CO]2 · Sb2F4O shows the existence of linked units urea-Sb2F4O which show the Sb2F4O entity, not yet known. Crystal structure was solved with a singlecrystal X-ray diffraction study (the final R value is 0.046). The Sb2F4O unit is composed of a symmetric and short SbOSb bridge, and of four fluorine atoms, two being bonded to each antimony atom and situated in trans position relative to the SbOSb bridge. The bridge bond strength is assigned to a pπdπ overlap.  相似文献   

16.
Various 1H,1H-perfluoroalkanes (RFCF2CH2F, RF = CF3, C2F5, C4F9, C5F11, C6F13, C10F21) were metallated using LDA in a THF solution of ZnCl2 at RT or −78 °C to produce the corresponding perfluoroalkenylzinc reagents (RFCFCFZnCl) in a cis-selective fashion. An increased yield (75–83%) and cis-selectivity (>89%) of the perfluoroalkenylzinc reagents were observed for metallation reactions performed at −78 °C. The cis selectivity was excellent for 1H,1H-perfluoroalkanes with larger RF groups (C4F9, C5F11, C6F13, >96%). The cis-perfluoroalkenylzinc [(E)-RFCFCFZnCl] reagents were coupled with aryl iodides to obtain cis-1-arylperfluoroalkenes [(Z)-RFCFCFAr] in 71–95% isolated yields. The cis-perfluoroalkenylzinc reagents upon iodinolysis produced cis-1-iodoperfluoroalkenes [(E)-RFCFCFI] in 68–70% isolated yield.  相似文献   

17.
Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(VM)n-RF] underwent the sol-gel reaction under alkaline conditions in the presence of anatase titanium oxide nanoparticles (an-TiO2) in tetrahydrofuran to give the corresponding fluorinated oligomer/anatase titanium oxide nanocomposites [RF-(VM-SiO2)n-RF/an-TiO2]. Crystalline structure of an-TiO2 in the nanocomposites thus obtained was found to keep completely its structure without phase transformation to rutile even after calcination at 1000 °C, although crystalline structure of the original an-TiO2 nanoparticles underwent a complete phase transformation to the rutile under similar conditions. Interestingly, RF-(VM-SiO2)n-RF/an-TiO2 nanocomposites before and after calcination at 1000 °C exhibited the similar photocatalytic activity for the decolorization of methylene blue under UV light irradiation.  相似文献   

18.
Single-crystal X-ray diffraction analysis was used to determine the structure of a racemic diastereomer of the agricultural fungicide propiconazole [1-(2-(2,4-dichlorophenyl)-4-n-propyl-1,3-dioxolane-2-yl-methyl)-1-H-1,2,4-triazole] and of two by-products (a symmetrical 1,3,4-triazole racemic-constitutional isomer and a propiconazole ditriazole analogue). All three crystalline racemic-diastereomers had (2R,4S)/(2S,4R)-stereochemistry in which then-propyl group was observed in atrans-to-phenyl disposition. Propiconazole (2R,4S)/(2S,4R)-diastereomer gives crystals belonging to the monoclinic space group P21,/a, and, at 293 K,a=8.1192(3),b=18.9769(6),c=10.7137(4) å,Β=99.765(3)?,V=1626.8(1) å3, Z=4,R(F)=0.060, andR w(F)=0.058. The constitutional isomer by-product (2R,4S)/(2S,4R)-1-(2-(2,4-dichlorophenyl)-4-n-pro-pyl-1,3-dioxolane-2-yl-methyl)-1-H-1,3,4-triazole gives crystals belonging to the monoclinic space group P21/n, and, at 293 K,a=11.1763(6),b=10.7716(4),c=14.5804(8) å,Β=107.445(4)?,V=1674.6(1) å3, Z=4,R(F)=0.043, andR w(F)=0.043. The ditriazole byproduct (2R,4S)/(2S,4R)-1-(2-(2-chloro-4-(1,2,4-triazole-1-yl)phenyl)-4-n-propyl-1,3-dioxolane-2-yl-methyl)-1-H-1,2,4-triazole gives crystals belonging to the triclinic space group 1, and, at 193 K,a=5.3329(8),b=8.3738(7),c=20.240(2) å, α=84.213(6)?,Β=87.20(1)?,γ=86.23(1)?,V=896.5(2) å3, Z=2,R(F)=0.046, andR w(F)=0.051. The presence of both propiconazole (2R.4S)- and (2S,4R)-enantiomers enables the formation of a crystalline racemic modification, while the diastereomeric propiconazole (2R,4R)- and (2S,4S)-enantiomers are viscous oils. In the absence of its enantiomorphic partner, the propiconazole (2R,4S)- or (2S,4R)-enantiomers remain as viscous oils rather than form chiral crystals.  相似文献   

19.
Transition Metal Peroxofluoro Complexes. VII. Peroxofluorokryolithes A3Ti(O2)F5 (A = K, Na) and K2NaTi(O2)F5. Crystal Structure of K3Ti(O2)F5 Peroxofluorokryolithes A3Ti(O2)F5 (A = K, Na) and K2NaTi(O2)F5 were prepared at pH 4.5–6 by adding H2O2 and AOH/AF to solutions of TiO2 in hydrofluoric acid or aqueous solutions of TiF4. In the range of pH 3–4.5 exist phases of peroxofluoro-kryolithes with variations in stoichiometrie. A single crystall X-ray structure analysis of K3Ti(O2)F5 (Fm3m, a = 883.6(1) pm) yielded a disordered kryolithstructure (R = 0.020, RW = 0.017). Na3Ti(O2)F5 was found to crystallize in two monoclinic low-temperature – and one cubic high-temperature modifications. K2NaTi(O2)F5 crystallizes cubic (Fm3m) with a = 847.8(1) pm. Vibrational spectra have been measured and thermal behavior was studied by DTA/DTG and high-temperature guinier. At pH 9.5 K3Ti(O2)2F3 has been synthesized  相似文献   

20.
New experimental results on perfluoroalkylation of C60 and C70 with the use of RfI (Rf = CF3, C2F5, n-C3F7, n-C4F9, and n-C6F13), along with a critical overview of the existing synthetic methods, are presented. For the selected new fullerene (Rf)n compounds we report spectroscopic, electrochemical and structural data, including improved crystallographic data for the isomers of C70(C2F5)10 and C60(C2F5)10, and the first X-ray structural data for the dodecasubstituted perfluoethylated C70 fullerene, C70(C2F5)12, which possesses unprecedented addition pattern.  相似文献   

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