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1.
Fluorinated polyacrylats with side group containing vinylidene fluoride (VDF) units (CF3(CF2)n (CH2CF2)m, n = 3, 5; m = 1, 2) were successfully synthesized. The water and oil repellency properties of these polymers are similar to those of fluorinated polyacrylate with side group containing long perfluorooctyl group (CF3(CF2)7). The thermal telomerization of CF3(CF2)5I and CF3(CF2)3I with vinylidene fluoride (VDF) provided CF3(CF2)5CH2CF2I (1b) and CF3(CF2)3CH2CF2CH2CF2I (1c), respectively. The addition of 1b with ethylene followed by hydrolysis gave CF3(CF2)5CH2CF2CH2CH2OH (2b). Treatment of 1c with ethyl vinyl ether in the presence of Na2S2O4 followed by reduction produced CF3(CF2)3CH2CF2CH2CF2CH2CH2OH (2c). Fluoroacrylates 3b-d were prepared by acrylation of the corresponding fluoroalcohols 2b-d. The semi-continuous process emulsion co-polymerization of 3a-d with octadecyl acrylate and 2-hydroxylethyl acrylate initiated by (NH4)2S2O8 in the presence of a mixture emulsifiers of polyoxyethylene(10)nonyl phenyl ether (TX-10) and sodium lauryl sulfate provided stable latexes 4a-d, respectively. The water and oil repellency properties of 4b (Rf: CF3(CF2)5CH2CF2) and 4c (Rf: CF3(CF2)3CH2CF2CH2CF2) containing vinylidene fluoride (VDF) units were similar to those of 4a (Rf: CF3(CF2)7) containing long perfluoroalkyl group and much better than those of polymer 4d (Rf: CF3(CF2)3) with short perfluoroalkyl chain. Thus, polyacrylates containing vinylidene fluoride units showed promising aspects as the alternatives to the currently used water and oil repellent agents with long perfluoroalkyl chains.  相似文献   

2.
A polystyrene with pendant calix[4]pyrroles was prepared via ‘click reaction’ strategy. First, a poly(styrene-co-chloromethylstyrene) with approximately 12% of chloro groups was prepared by conventional free radical polymerisation. The chloro groups were then converted to azido groups using NaN3 in N,N-dimethylformamide. An alkyne-functionalised calix[4]pyrrole was then coupled to the azido-functionalised polystyrene by click chemistry with high efficiency. The resulting polystyrene with pendant calix[4]pyrroles was used to extract fluoride and chloride anions (as their tetrabutylammonium salts) from their aqueous solutions to organic media.  相似文献   

3.
Thermal decarbonylation of the acyl compounds [Mn(CO)5(CORF)] (RF=CF3, CHF2, CH2CF3, CF2CH3) yielded the corresponding alkyl derivatives [Mn(CO)5(RF)], some of which have not been previously reported. The compounds were fully characterized by analytical and spectroscopic methods and by several single-crystal X-ray diffraction studies. The solution-phase IR characterization in the CO stretching region, with the assistance of DFT calculations, has allowed the assignment of several weak bands to vibrations of the [Mn(12CO)4(eq-13CO)(RF)] and [Mn(12CO)4(ax-13CO)(RF)] isotopomers and a ranking of the RF donor power in the order CF3<CHF2<CH2CF3≈CF2CH3. The homolytic Mn−RF bond cleavage in [Mn(CO)5(RF)] at various temperatures under saturation conditions with trapping of the generated RF radicals by excess tris(trimethylsilyl)silane yielded activation parameters ΔH and ΔS that are believed to represent close estimates of the homolytic bond dissociation thermodynamic parameters. These values are in close agreement with those calculated in a recent DFT study (J. Organomet. Chem. 2018 , 864, 12–18). The ability of these complexes to undergo homolytic Mn−RF bond cleavage was further demonstrated by the observation that [Mn(CO)5(CF3)] (the compound with the strongest Mn−RF bond) initiated the radical polymerization of vinylidene fluoride (CH2=CF2) to produce poly(vinylidene fluoride) in good yields by either thermal (100 °C) or photochemical (UV or visible light) activation.  相似文献   

4.
Abstract

The reactions of a variety of electrophiles with the N-silyl-P-trifluoroethoxyphosphoranimine anion Me3Sin°P(Me)(OCH2CF3)CH? 2 (1a), prepared by the deprotonation of the dimethyl precursor Me3SiN[dbnd]P(OCH2CF3)Me2 (1) with n-BuLi in Et2O at-78°C, were studied. Thus, treatment of 1a with alkyl halides, ethyl chloroformate, or bromine afforded the new N-silylphosphoranimine derivatives Me3SiN[dbnd]P(Me)(OCH2CF3)CH2R [2: R = Me, 3: R = CH2Ph, 4: R = CH[sbnd]CH2, 5: R = C(O)OEt, and 6: R = Br]. In another series, when 1a was allowed to react with various carbonyl compounds, 1,2-addition of the anion to the carbonyl group was observed. Quenching with Me3SiCl gave the O-silylated products Me3SiN[dbnd]P(Me)(OCH2CF3)CH2°C(OSiMe3)R1R2 [7: R 1 = R 2 = Me; 8: R 1 = Me, R 2 = Ph; 9: R1 = Me, R 2 = CH[sbnd]CH2; and 10: R 1 = H, R 2 = Ph]. Compounds 2–10 were obtained as distillable, thermally stable liquids and were characterized by NMR spectroscopy (1H, 13C, and 31P) and elemental analysis.  相似文献   

5.
本文以对叔丁基杯[8]芳烃(H8C8A)为配体,在溶剂热条件下制得了3个3d-5f化合物,[Co2Th4(HC8A)2O2(OH)2(DMF)6](1)、[Ni2Th5(H2C8A)(C8A)O4(OH)2(DMF)5(CH3OH)2](2)、[Zn2Th6(HC8A)(C8A)O5(CH3O)(C3H6NO22(DMF)5(CH3OH)](3)(其中H8C8A=对叔丁基杯[8]芳烃,DMF=N,N-二甲基甲酰胺)。X-射线单晶测试表明,这3个化合物均为2个以尾对尾方式排列的杯[8]芳烃分子中间夹1个3d-5f核簇的三明治型结构。杯[8]芳烃均表现为双锥式构型,且每个锥式空腔下缘结合1个钍离子,双锥的连接处及2个杯芳烃分子之间由过渡金属离子或钍离子连接。不同过渡金属离子不同的配位环境导致3种不同核簇的形成。化合物1的磁性研究表明,该化合物在低温下表现出弱铁磁性相互作用。  相似文献   

6.
The fluorocarbon soluble, binuclear ruthenium(I) complexes [Ru(μ-O2CMe)(CO)2LF]2, where LF is the perfluoroalkyl substituted tertiary phosphine, P(C6H4-4-CH2CH2(CF2)7CF3)3, or P(CH2CH2(CF2)5CF3)3, were synthesized and partition coefficients for the complexes in fluorocarbon/hydrocarbon biphases were determined. Catalytic hydrogenation of acetophenone to 1-phenylethanol in benzotrifluoride at 105 °C occured in the presence of either [Ru(μ-O2CMe)(CO)2P(C6H4-4-CH2CH2(CF2)7CF3)3]2 (1) or [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 (2). The X-ray crystal structure of [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 was determined. The compound exhibited discrete regions of fluorous and non-fluorous packing.  相似文献   

7.
The binding studies of calix[4]pyrroles (16) with fluoro, chloro, bromo, iodo and sulphato anions generated from normal-tetrabutylammoniumfluoride, normal-tetrabutylammoniumchloride, normal-tetrabutylammoniumbromide, normal-tetrabutylammoniumiodide, and normal-tetrabutylammoniumsulphate respectively were investigated by electrospray ionization mass spectrometry (ESI-MS) in dichloromethane–acetonitrile in negative ion mode. The efficacy of a particular calix[4]pyrrole to bind with anions was found maximum at low cone voltage of the instrument, at high cone voltage the binding was suppressed due to removal of anion from the cavity of the macrocycles. The binding strength was found inversely proportional to the size of anion for a particular calix[4]pyrrole. The fragmentation pattern of calix[4]pyrrole was observed at higher cone voltage of ESI-MS and was interpreted. The association constants of calix[4]pyrroles and anions obtained from electronic transition studies were in good agreement with that observed from 1H NMR titration studies.  相似文献   

8.
In this contribution we report on fluorotrimethyl[(Z)-pentafluoropropen-1-yl]phosphorane as a phosphorus based fluorinating reagent. Its solid state structure can be described as a trigonal bipyramid featuring elongated axial bonds due to the formation of a 3-center 4-electron bond. Abstraction of the fluoride ion leads to a shortening of the axial P–C bond. Thus the title compound can be utilized for substitution of bromine with fluorine and for the transfer of fluoride ions onto electrophilic compounds. Reaction with Sn(C2F5)2Br2 afforded salt [P(CH3)3(C3F5)]2[Sn(C2F5)2F4]. When fluorotrimethyl[(Z)-pentafluoropropen-1-yl]phosphorane was treated with P(C2F5)2F the primarily produced anion is sufficiently nucleophilic to attack the propenyl group of the cation in β-position to the phosphorus atom to yield zwitterionic [Me3PCF=C(CF3)–PF3(C2F5)2].  相似文献   

9.
Abstract

Single halogen atom (i. e. I, Br, Cl and F) substituted calix[4]pyrroles, compounds 2, 3, 4 and 5, were synthesized. Studies of these systems reveal that replacement of a single β-pyrrolic hydrogen atom can increase the anion binding ability of calix[4]pyrroles for a variety of anions (e. g. Cl?, Br?, H2PO4 ? and HSO? 4) relative to normal non-halogen substituted calix[4]pyrrole 1. In the case of chloride anion, the expected relative affinity sequence of 5 > 4 > 3 > 2 was observed. This was not found to be true for Br?, H2PO? 4, and HSO? 4. Here, the chlorine substituted calix[4]pyrrole 4 was found to display a slightly higher affinity in the case of each anion than the fluorine-bearing derivative 5. This was rationalized in terms of intermolecular NH … F hydrogen bonding interactions being present in CD2Cl2 solutions of 5. Support for this latter conclusion came from concentration and temperature-dependent NMR spectroscopic studies.

A matched set of mono halogen substituted calix[4]pyrroles was used to study in detail, the extent to which halogen substituents may be used to fine-tune the anion binding properties of calix[4]pyrroles.  相似文献   

10.
Solutions of the fluorous alkyl halides Rf8(CH2)mX (Rfn=(CF2)n?1CF3; m=2, 3; X=Cl, Br, I) in perfluoromethylcyclohexane or perfluoromethyldecalin are inert towards solid or aqueous NaCl, NaBr, KI, KCN, and NaOAc. However, halide substitution occurs in the presence of fluorous phosphonium salts (Rf8(CH2)2)(Rf6(CH2)2)3P+X? (X=I ( 1 ), Br ( 3 )) and (Rf8(CH2)2)4P+I? (10 mol %), which are soluble in the fluorous solvents under the reaction conditions (76–100 °C). Stoichiometric reactions of a) 1 with Rf8(CH2)2Br and b) 3 with Rf8(CH2)2I were conducted under homogenous conditions in perfluoromethyldecalin at 100 °C and yielded the same Rf8(CH2)2I/Rf8(CH2)2Br equilibrium ratio (≈60:40). This shows that ionic displacements can take place in extremely nonpolar fluorous phases and suggests a classical phase‐transfer mechanism for the catalyzed reactions. Interestingly, the nonfluorous salt (CH3(CH2)11)(CH3(CH2)7)3P+I? ( 4 ) also catalyzes halide substitutions, but under triphasic conditions with 4 suspended between the lower fluorous and upper aqueous layers. NMR experiments established very low solubilities in both phases, which suggests interfacial catalysis. Catalyst 1 is easily recycled, optimally by simple precipitation onto teflon tape.  相似文献   

11.
Electron impact fragmentation patterns were obtained for perfluoroalkylether nitriles, C,F,O[CF(CF3)CFIO]ICF(CF3)CN (x = 1 and 2), perfluoroalkylether acyl halides, CSF,OCF(CF,)-CF2OCF(CF3)COX (X = F and Cl), n-perfluorooctanonitrile and n-perfiuorooctanoyl chloride. The perfluoroalkyl and perfluoroalkylether nitriles afforded ions characteristic of the nitrile function. The major fragment from the acyl chlorides was the [COClJ]+ ion; the presence of chlorine was evidenced also by rearrangement ions of the general form [RfCl] t. The perfluoroalkylether compounds appeared to undergo a typical fragmentation governed by the cleavage of the carbon-oxygen bond.  相似文献   

12.
Syntheses and NMR Spectroscopic Ivestigations of Salts containing the Novel Anions [PtXn(CF3)6‐n]2— (n = 0 ‐ 5, X = F, OH, Cl, CN) and Crystal Structure of K2[(CF3)2F2Pt(μ‐OH)2PtF2(CF3)2]·2H2O The first syntheses of trifluoromethyl‐complexes of platinum through fluorination of cyanoplatinates are reported. The fluorination of tetracyanoplatinates(II), K2[Pt(CN)4], and hexacyanoplatinates(IV), K2[Pt(CN)6], with ClF in anhydrous HF leads after working up of the products to K2[(CF3)2F2Pt(μ‐OH)2PtF2(CF3)2]·2H2O. The structure of the salt is determined by a X‐ray structure analysis, P21/c (Nr. 14), a = 11.391(2), b = 11.565(2), c = 13.391(3)Å, β = 90.32(3)°, Z = 4, R1 = 0.0326 (I > 2σ(I)). The reaction of [Bu4N]2[Pt(CN)4] with ClF in CH2Cl2 generates mainly cis‐[Bu4N]2[PtCl2(CF3)4] and fac‐[Bu4N]2[PtCl3(CF3)3], but in contrast that of [Bu4N]2[Pt(CN)6] with ClF in CH2Cl2 results cis‐[Bu4N]2[PtX2(CF3)4], [Bu4N]2[PtX(CF3)5] (X = F, Cl) and [Bu4N]2[Pt(CF3)6]. In the products [Bu4N]2[PtXn(CF3)6‐n] (X = F, Cl, n = 0—3) it is possibel to exchange the fluoro‐ligands into chloro‐ and cyano‐ligands by treatment with (CH3)3SiCl und (CH3)3SiCN at 50 °C. With continuing warming the trifluoromethyl‐ligands are exchanged by chloro‐ and cyano‐ligands, while as intermediates CF2Cl and CF2CN ligands are formed. The identity of the new trifluoromethyl‐platinates is proved by 195Pt‐ and 19F‐NMR‐spectroscopy.  相似文献   

13.
The fluorocarbon soluble, binuclear ruthenium(I) complexes [Ru(μ-O2CMe)(CO)2LF]2, where LF is the perfluoroalkyl substituted tertiary phosphine, P(C6H4-4-CH2CH2(CF2)7CF3)3, or P(CH2CH2(CF2)5CF3)3, were synthesized and partition coefficients for the complexes in fluorocarbon/hydrocarbon biphases were determined. Catalytic hydrogenation of acetophenone to 1-phenylethanol in benzotrifluoride at 105 °C occured in the presence of either [Ru(μ-O2CMe)(CO)2P(C6H4-4-CH2CH2(CF2)7CF3)3]2 (1) or [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 (2). The X-ray crystal structure of [Ru(μ-O2CMe)(CO)2P(CH2CH2(CF2)5CF3)3]2 was determined. The compound exhibited discrete regions of fluorous and non-fluorous packing.  相似文献   

14.
Abstract

The System CF3I/Me3P is re-investigated and Me2PCF3, Me4P+γ, (CF3)2PMe3, Me3PI2, [Me3(CF3)P]+γ are found as products. Using CF3Br/P(NEt2)3 the phosphines R1 2PCF3 and R1P(CF3)2 (e.g. R1 = Me, iPr, NEt2) can be obtained which are precursors either for phosphoranes (e.g. 1,2λ5σ5-oxaphosphetanes) or phosphonium salts (e.g. [R1 2(Me)PCF3]+X? or [R1(Me)P(CF3)2X?]. The latter are deprotonated to furnish methylene phosphoranes R1 2(CH2=)PCF3 or R1(CH2=)P(CF3)2, reactive synthons. From CF3Br/P(NEt2)3/P(OPh)3 the phosphine P(CF3)3 is available, which turned out to be a potent electrophile. Amido phospites ROP(NEt2)2 and halides R2X (R2=CCl2CF3, X=Cl; R2=CF=CFCF3, X=F; R2=C6F5, X=Br, I; R2=C(CF3)3, X=Br; R2=SCF3, X=CF3) undergo an ARBUZOV reaction.  相似文献   

15.
Extended cavity calix[4]pyrroles and a calix[6]pyrrole were synthesized by cyclization of 5-methyl-5-(4-nitrophenyl)dipyrromethane with acetone in the presence of acid. The solid-state structures of the novel macrocycles were determined by X-ray crystallography. The host-guest chemistry of these receptors towards halide ions was investigated in solution by 1H NMR titration techniques and compared with those of the meso-octamethylcalix[4]pyrrole and meso-dodecamethylcalix[6]pyrrole. The binding of chloride anions was observed to occur with different affinities on the two faces of the novel calix[6]pyrrole derivative described here.  相似文献   

16.
Twenty nine bis(fluoroalkyl) phosphates (RFO)2P(O)OR were prepared in 18-75% yield by treating phosphorochloridates (RFO)2P(O)Cl, where RF was HCF2CH2, HCF2CF2CH2, H(CF2)4CH2, C2F5CH2, C3F7CH2, (CF3)2CH, (FCH2)2CH and (CH3)2CF3C with methanol, ethanol, propanol and isopropanol in diethyl ether in the presence of triethylamine. The bulky chloridate [(CH3)2CF3CO]2P(O)Cl reacted with methanol, ethanol and propanol, but not with isopropanol - even on heating in the presence of the catalyst 4-dimethylaminopyridine - due to steric hindrance at phosphorus. The relative reactivities of three of the chloridates decreased in the order [(CF3)2CHO]2P(O)Cl > [(FCH2)2CHO]2P(O)Cl > [(CH3)2CF3CO]2P(O)Cl. Also described is the synthesis of phosphates (CF3CH2O)2P(O)OCH2R, where R = CH2Br, CH2Cl, CH2F and CHF2, and diphosphates [H(CF2)nCH2O]2P(O)OCH2(CF2)2CH2OP(O)[OCH2(CF2)nH]2, where n = 1, 2 and 4.  相似文献   

17.
Ring closure of 1,2-bis(1-pyrrolylmethyl)benzene in the acid-catalysed condensation with acetone yields the 1,5-diazacyclononatriene [ O -C6H4(CH2NC4H3-2)2C(CH3)2] as the sole identifiable product. The twisted or saddle conformation of the 1,5-diazacyclononatriene, which was confirmed by X-ray crystal structure determination, is conformationally rigid in solution. The conformation of the 1,5-diazacyclononatriene prevents the formation of the target N,N′-bridged calix[4]pyrrole by further acid-catalysed condensation with acetone, the reaction affording unidentified oligomers/polymers instead. The acid-catalysed condensation of 1,3- and 1,4-bis(1-pyrrolylmethyl)benzene with acetone also yields unidentified oligomers/polymers.  相似文献   

18.
This minireview updates non-exhaustive recent strategies of synthesis of original fluorosurfactants potentially non-bioaccumulable. Various strategies have been focused on (i) the preparation of CF3–X–(CH2)n–SO3Na (with X = O, C6H4O or N(CF3) and n = 8–12), (ii) the oligomerization of hexafluoropropylene oxide (HFPO) to further synthesize oligo(HFPO)–CF(CF3)CO–RH (where RH stands for an hydrophilic chain); (iii) the telomerization of vinylidene fluoride (VDF) with 1-iodopentafluoroethane or 1-iodononafluorobutane to produce CnF2n+1–(VDF)2–CH2CO2R (n = 2 or 4, R = H or NH4), (iv) the radical telomerization of 3,3,3-trifluoropropene (TFP) with isoperfluoropropyliodide or diethyl hydrogenophosphonate to prepare (CF3)2CF(TFP)x–RH or CF3–CH2–CH2–(TFP)y–P(O)(OH)2, and (v) the radical cotelomerization of VDF and TFP, or their controlled radical copolymerization in the presence of (CF3)2CFI or a fluorinated xanthate. In most cases, the surface tensions versus the surfactant concentrations have been assessed. These above strategies led to various highly fluorinated (but yet not perfluorinated) telomers whose chemical changes enabled to obtain original surfactants as novel alternatives to perfluorooctanoic acid (PFOA), ammonium perfluorooctanoate (APFO), or perfluorooctylsulfonic acid (PFOS) regarded as bioaccumulable, persistent, and toxic.  相似文献   

19.
A series of calix[4]pyrrole meso-substituted Schiff bases was synthesized with 5α,10α-di(4- hydroxylphenyl)calix[4]pyrrole or 5α,15β-di(4-hydroxylphenyl)calix[4]pyrrole as starting materials. The synthetic routes included alkylation with methyl a-chlroroaceate, ammonolysis with alkylene diamine, and condensation with salieylladehyde or 2-hydroxynaphthaldehyde. The crystal structures of the new calix[4]pyrroles and their Schiff bases were determined by X-ray diffraction. The coordination properties of the representative ealix[4]pyrrole Sehiff bases to transition metal ions were also investigated by UV-Vis spectra.  相似文献   

20.
Using P. T. C. or cosolvents, both perfluoroalkyl iodides such as Cl(CF2),nI (n=2, 4, 6, 1a-1c), H(CF2)8I (1d), CF3(CF2)nI (n=3, 5, 7, 1e-1g), and α. ω-perfluoroalkylene diiodides such as (ICF2CF2)2O (4a), I (CF2)nI (n=6, 8, 10, 4b-4d) reacted smoothly with sodium dithionite in aqueous solution under mild conditions to give the corresponding perfluoroalkanesulfinates Cl(CF2)nSO2Na (n=2, 4, 6, 2a-2c), H(CF2)8SO2Na (2d), CF3(CF2)nSO2Na (n=3, 5, 7, 2e-2g), α, ω-perfluoroalky-lenedisulfinates O (CF2CF2SO2K)2 (5a), and KO2S(CF2)nSO3K (n=6, 8, 10, 6b-6d) in moderate to high yields. These sulfinates were converted to the corresponding sulfonyl chlorides by reacting with chlorine in the usual way. Thus the discovery of the new reagent renders sulfinatodeiodination a practical method for the synthesis of perfluorosulfinic and perfluorosulfonic acids and their derivatives from the corresponding perfluoroalkyl iodides.  相似文献   

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