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1.
Two routes to RFIF6 compounds were investigated: (a) the substitution of F by RF in IF7 and (b) the fluorine addition to iodine in RFIF4 precursors. For route (a) the reagents C6F5SiMe3, C6F5SiF3, [NMe4][C6F5SiF4], C6F5BF2, and 1,4-C6F4(BF2)2 were tested. C6F5IF4 and CF3CH2IF4 were used in route (b) and treated with the fluoro-oxidizers IF7, [O2][SbF6]/KF, and K2[NiF6]/KF. The observed sidestep reactions in case of routes (a) and (b) are discussed. Interaction of C6F5SiX3 (X = Me, F), C6F5BF2, 1,4-C6F4(BF2)2 with IF7 gave exclusively the corresponding ring fluorination products, perfluorinated cyclohexadiene and cyclohexene derivatives, whereas [NMe4][C6F5SiF4] and IF7 formed mixtures of C6FnIF4 and C6FnH compounds (n = 7 and 9). CF3CH2IF4 was not reactive towards the fluoro-oxidizer IF7, whereas C6F5IF4 formed C6FnIF4 compounds (n = 7 and 9). C6F5IF4 and CF3CH2IF4 were inert towards [O2][SbF6] in anhydrous HF. CF3CH2IF4 underwent C-H fluorination and C-I bond cleavage when treated with K2[NiF6]/KF in HF. The fluorine addition property of IF7 was independently demonstrated in case of perfluorohexenes. C4F9CFCF2 and IF7 underwent oxidative fluorine addition at −30 °C, and the isomers (CF3)2CFCFCFCF3 (cis and trans) formed very slowly perfluoroisohexanes even at 25 °C. The compatibility of IF7 and selected organic solvents was investigated. The polyfluoroalkanes CF3CH2CHF2 (PFP), CF3CH2CF2CH3 (PFB), and C4F9Br are inert towards iodine heptafluoride at 25 °C while CF3CH2Br was slowly converted to CF3CH2F. Especially PFP and PFB are new suitable organic solvents for IF7.  相似文献   

2.
The relative fluoride donor ability: C6F5BrF2 > C6F5IF2 > C6F5IF4 was outlined from reactions with Lewis acids of graduated strength in different solvents. Fluoride abstraction from C6F5HalF2 with BF3·NCCH3 in acetonitrile (donor solvent) led to [C6F5HalF·(NCCH3)n][BF4]. The attempted generation of [C6F5BrF]+ from C6F5BrF2 and anhydrous HF or BF3 in weakly coordinating SO2ClF gave C6F5Br besides bromoperfluorocycloalkenes C6BrF7 and 1-BrC6F9. In reactions of C6F5IF2 with SbF5 in SO2ClF the primary observed intermediate (19F NMR, below 0 °C) was the 4-iodo-1,1,2,3,5,6-hexafluorobenzenium cation, which converted into C6F5I and 1-IC6F9 at 20 °C. The reaction of C6F5IF4 with SbF5 in SO2ClF below −20 °C gave the cation [C6F5IF3]+ which decomposed at 20 °C to C6F5I, 1-iodoperfluorocyclohexene, and iodoperfluorocyclohexane. Principally, the related perfluoroalkyl compound C6F13IF4 showed a different type of products in the fast reaction with AsF5 in CCl3F (−60 °C) which resulted in C6F14. Intermediate and final products of C6F5HalFn−1 (n = 3, 5) with Lewis acids were characterized by NMR in solution. Stable solid products were isolated and analytically characterized.  相似文献   

3.
Previously unknown polyfluorocyclohexenyl, and acyclic perfluoroalkenyliodine tetrafluorides were prepared in high yields. Perfluorocyclohex-1-enyliodine tetrafluoride was obtained from pentafluoroiodobenzene using XeF2-NbF5 in aHF. The reaction of C6F5I with the weaker fluorooxidant XeF2-BF3 in 1,1,1,3,3-pentafluorobutane (PFB) yielded C6F5IF2, perfluorocyclohexa-1,4-dienyliodine difluoride, C6F5IF4, perfluorocyclohexa-1,4, and 1,3-dienyliodine tetrafluoride as intermediate products on parallel reaction routes. Both perfluoroalkenyl iodides, cis- and trans-(CF3)2CFCFCFI, reacted with XeF2-BF3 in PFB to give the corresponding perfluoroalkenyliodine tetrafluorides, cis- and trans-(CF3)2CFCFCFIF4. Even perfluoroalkyl iodides can be fluorinated by this reagent as was demonstrated by the preparation of C6F13IF4 from C6F13I. Generally, the CFCIFn fragment (n = 0, 2, or 4) in cyclic or acyclic perfluoroalkenyliodine compounds RFIFn did not undergo a transformation to the corresponding perfluoroalkyliodine compound. Furthermore, no perfluoroorganoiodine hexafluorides were detected in reactions with the fluorooxidant XeF2-aHF or BF3 or NbF5.  相似文献   

4.
Fluorinated organodifluoroboranes RfBF2 are in general suitable reagents to transform XeF2 and RIF2 into the corresponding onium tetrafluoroborate salts [RfXe][BF4] and [R(Rf)I][BF4], respectively. (4-C5F4N)BF2 and trans-CF3CFCFBF2 which represent boranes of high acidity form no Xe-C onium salts in reactions with XeF2 but give the desired iodonium salts with RIF2 (R = C6F5, o-, m-, p-C6FH4). The reaction of (4-C5F4N)BF2 with XeF2 ends with a XeF2-borane adduct. C6F5Xe(4-C5F4N), the first Xe-(4-C5F4N) compound, was obtained when C6F5XeF was reacted with Cd(4-C5F4N)2. We describe the synthesis of (4-C5F4N)IF2 and reactions of (4-C5F4N)IF2 and C6F5IF2 with (4-C5F4N)BF2. Analogous to [(4-C5F4N)2I][BF4] and [C6F5(4-C5F4N)I][BF4] aryl(perfluoroalkenyl)iodonium salts [R(R′)I][BF4] were obtained from RIF2 (R = C6F5, o-, m-, p-C6FH4) and R′BF2 (R′ = trans-CF3CFCF, CF2CF). The gas phase fluoride affinities pF of selected fluoroorganodifluoroboranes RfBF2 and their hydrocarbon analogs are calculated (B3LYP/6-31+G*) and discussed with respect to their potential to introduce Rf-groups into hypervalent EF2 bonds. Four aspects which influence the transformation of hypervalent EF2 bonds (E = Xe, R′I) under the action of Lewis acidic reagents RAFn−1 (A = B, P; n = 3, 5) into the corresponding [RE][AFn+1] salts are presented and the important role of the acidity is emphasized. Fluoride affinities may help to plan the introduction of organo groups into EF2 moieties and to expand the types of acidic reagents. Thus C6H5PF4 with a pF value comparable to that of RfBF2 compounds is able to introduce the C6H5 group into RIF2 (R = C6F5, p-C6FH4).  相似文献   

5.
Phosphonic acids [(HO)2P(O)C2H4CnF2n+1] (n = 4, 6) and [(HO)2P(O)C6H4-4-CnF2n+1] (n = 0, 1, 6) have been prepared in good yields. Deprotonation and reaction with cis-[PtCl2(PPh3)2] affords fluorinated platinum complexes which have been characterised by elemental analysis, mass spectrometry, IR and NMR spectroscopies. The structures of [Pt{O2P(O)C6H4-4-F}(PPh3)2], [Pt{O2P(O)C6H4-4-CF3}(PPh3)2] and [Pt{O2P(O)C2H4C6F13}(PPh3)2] have been determined by single crystal X-ray diffraction.  相似文献   

6.
Five novel phosphate-type hybrid surfactants, CmF2m+1C6H4CH[OPO2(OC6H5)Na]CnH2n+1 (FmPHnPPhNa: m = 4, 6, 8; n = 3, 5; C6H4 = p-phenylene, C6H5 = phenyl), have been synthesized. When compared with sulfate-type hybrid surfactants, CmF2m+1C6H4CH(OSO3Na)CnH2n+1 (C6H4 = p-phenylene), the new hybrid surfactants are found to have comparable abilities to lower surface tension of water. The critical micelle concentrations of FmPHnPPhNa follow Klevens rule and their occupied areas per molecule increase with increasing m and n. Calcium hydroxyapatite (CaHAp) pellets modified with FmPH3PPhNa gives high hydrophobic and lipophobic surfaces. The hybrid surfactants are expected as new dental reagents for oral hygiene.  相似文献   

7.
A variety of fluorinated surfactants soluble in organic solvent were prepared, including C8F17SO2NHCnH2n+1 (n = 2, 4, 6, 8, 10), C8F17SO2NHR (R = C6H11, C6H5), C8F17SO2N(CnH2n+1)2 (n = 1, 2, 3, 4) and C8F17SO2NH(CH2)nNHO2SC8F17 (n = 6, 10). Their surface activities in various organic solvents were determined by surface tension measurement. The results showed that these fluorinated surfactants can reduce the surface tension of both polar and non-polar organic solvents. In general, organic solvents with strong polarity or long alkyl chain are beneficial to increase the surface activity of these polar fluorinated surfactants. By comparing fluorinated surfactants with the same fluorocarbon segment and connecting group, C8F17SO2N(CnH2n+1)2 (n = 1, 2, 3, 4) showed lower surface activity in organic solvents than C8F17SO2NHCnH2n+1 (n = 2, 4, 6, 8) with an equal carbon number of the solvophilic group. Through surface tension vs. concentration curves given for N-octyl perfluorooctanesulfonamide in various organic solvents, a break point like the critical micelle concentration of ordinary surfactants in aqueous solutions was observed, and the effect of the different types of organic solvents on adsorption and aggregation behavior was also studied.  相似文献   

8.
The new “heavy fluorous” cyclopentadienes C5H6−n[M(C2H4C6F13)3]n (M = Si, n = 1 (3); n = 2 (4) and M = Sn, n = 1 (10)) were synthesized by reaction of cyclopentadienyl lithium with BrSi(C2H4C6F13)3 (2) or commercial BrSn(C2H4C6F13)3. Fluorous cyclopentadienes prepared in this manner contain three or six C6F13 groups, which significantly increase their solubility in perfluorinated solvents. They also provide intermediates for titanium complexes suitable for fluorous biphase catalysis. All three isomers of silylcyclopentadienes 3 and 4 were identified and fully characterized by two dimensional NMR spectroscopy, which was performed at low temperature. The allylic isomers 3a and 4a undergo degenerate metallotropic rearrangement. This fluxional behaviour was compared with the behaviour of previously prepared cyclopentadienes 6 and 7 (C5H6−n[SiMe2(C2H4C8F17)]n where n = 1, 2, respectively). The presence of allylic isomers 6a and 7a was further confirmed by Diels-Alder cycloaddition of the strong dienophile tetracyanoethylene (TCNE), providing compounds 8 and 9.  相似文献   

9.
A series of previously unknown asymmetrical fluorinated bis(aryl)bromonium, alkenyl(aryl)bromonium, and alkynyl(aryl)bromonium salts was prepared by reactions of C6F5BrF2 or 4-CF3C6H4BrF2 with aryl group transfer reagents Ar′SiF3 (Ar′ = C6F5, 4-FC6H4, C6H5) or perfluoroorganyl group transfer reagents RF′BF2 (RF = C6F5, trans-CF3CFCF, C3F7C≡C) preferentially in weakly coordinating solvents (CCl3F, CCl2FCClF2, CH2Cl2, CF3CH2CHF2 (PFP), CF3CH2CF2CH3 (PFB)). The presence of the base MeCN and the influence of the adducts RF′BF2·NCMe (RF = C6F5, CF3C≡C) on reactions aside to bromonium salt formation are discussed. Reactions of C6F5BrF2 with AlkF′BF2 in PFP gave mainly C6F5Br and AlkF′F (AlkF′ = C6F13, C6F13CH2CH2), presumably, deriving from the unstable salts [C6F5(AlkF′)Br]Y (Y = [AlkF′BF3]). Prototypical reactivities of selected bromonium salts were investigated with the nucleophile I-and the electrophile H+. [4-CF3C6H4(C6F5)Br][BF4] showed the conversion into 4-CF3C6H4Br and C6F5I when reacted with [Bu4N]I in MeCN. Perfluoroalkynylbromonium salts [CnF2n+1C≡C(RF)Br][BF4] slowly added HF when dissolved in aHF and formed [Z-CnF2n+1CFCH(RF)Br][BF4].  相似文献   

10.
Fluorophilic ethers having the structure RC(CF3)2O(CH2)3CnF2n + 1 are obtained in high yields, when F-tert-butyl alcohol (R = CF3), F-acetone hydrate (R = O(CH2)3CnF2n + 1), F-pinacol (R = C(CF3)2O(CH2)3CnF2n + 1) are reacted with 3-perfluoroalkyl-1-propanols (CnF2n + 1(CH2)3OH, n = 4, 6, 8, 10) in a Mitsunobu reaction (Ph3P/DIAD [i-PrO2CN = NCO2Pr-i]/ether). The parent lipophilic ethers with the structure of (CF3)3CO(CH2)3CnH2n + 1 were prepared analogously using the corresponding fatty alcohols and F-tert-butyl alcohol. To achieve ideal separations, products were transferred to orthogonal phases relative to the other reaction components using fluorous extraction, fluorous solid-organic liquid filtration, or steam-distillation. Selected physical properties including melting and boiling point, together with fluorous partition coefficients of these ethers were determined and the figures obtained were qualitatively analyzed using relevant thermodynamic theories. Some of these ethers are liquids with rather low freezing points and are miscible with fluorocarbon solvents.  相似文献   

11.
Pentafluorophenyliodine(III) Compounds. 2. Fluorine-Aryl Substitution Reactions on Iodinetrifluoride: Synthesis of Pentafluorophenyliodinedifluoride C6F5IF2 and Bis(pentafluorophenyl)iodonium Pentafluorophenylfluoroborates[(C6F5)2I]+[(C6F5)nBF4?n]? Mono- and disubstitution can be achieved in the fluorine-aryl substitution reaction on the low-temperature phase IF3 in CH2Cl2 at ?78°C depending on the aryl transfer reagent. With B(C6F5)3 [(C6F5)2I]+ [(C6F5)nBF4?n]? (68% yield) and with Cd(C6F5)2 C6F5IF2 (97% yield) is obtained whereas with C6F5SiMe3 no fluorine-aryl substitution takes place on IF3 even under basic conditions (EtCN or F? addition). At ?78°C in EtCN solution IF3 does not disproportionate but attacks the solvent under formation of HF.  相似文献   

12.
The reaction of 1,1′-bis(pentafluorophenyl)ferrocene with fluorous alkoxides having the general formula NaOCH2(CF2)nCF3 (n = 0, 2, 5, 7, and 8) afforded a series of ferrocenes of general formula {η5-4-[CF3(CF2)nCH2O]C6F4C5H4}2Fe (1). The reaction of 1,1′-bis(4-tetrafluoropyridyl)ferrocene with the same fluorous alkoxides afforded a series of ferrocenes of general formula (η5-4-{2,6-[CF3(CF2)nCH2O]2C5F2N}C5H4)2Fe (2). Perfluoro(methylcyclohexane)/toluene partition coefficients increase with the number (2 or 4) and length (n) of the fluorous substituent. Complexes 1a and 2a (both n = 0) were structurally characterized.  相似文献   

13.
Using silyl protected organic hydroxo compounds substitution of fluorine in IF5 is successful.Reacting IF5 with Si(OCH3)4 in CH3CN or SO2 using different molar ratios it was shown that in the series IF5?n(OCH3)n only the first member IF4(OCH3) (n=1) is stable enough to be isolated. The product in solution with n=2 bismutates to products with n=1 and n=3 if isolated as solids. The last one decomposes to the new oxo compound IF2O(OCH3) under elimination of CH3OCH3. With n=4,5 only redox reaction products could be isolated.IF2O(OCH3) can also be obtained by treating IF4(OCH3) with (CH3)6Si2O. Similarly reaction of IF5 with the disiloxane represents a new method to win IOF3. Excess of the oxygen transfer reagent leads to formation of IO2F and I2O5. An other oxo compound, IO(CH3COO)3, can be prepared by disolving IF5, IOF3 or IO2F in acetic acid anhydride.Reactions of IF5 with trimethylsilyl protected fluorinated benzoic acids RfCOOSi(CH3)3 (Rf = C6F5, 4HC6F4) appeared to be independent of the educts molar ratios because the only products are IF(RfCOO)4.In order to stabilize iodine (V) derivates with bifunctional chelating oxo ligands we applicated bis(trimethylsilyl) pinacolate, and in smooth reactions we yielded IF3[OC(CH3)2C(CH3)2O] and IF[OC(CH3)2  C(CH3)2O]2, in which iodine is part of five membered heterocyclic rings. The 19F-nmr-spectra are consistent with the diolate occupying the axiale and equatorial positions.An extension of the silyl method is the new synthesis of C6F5IF4 which could be obtained in the smooth reaction of IF5 with stochiometric amounts of Si(C6F5)4.  相似文献   

14.
The oxidation of C6F5I by oxidizers containing positive chlorine was investigated with the intention to prepare pentafluorophenyliodine (III) compounds: C6F5IX2, where X are halides or oxoderivatives. Using ClF, ClOCF3, Cl2/AlCl3 or Cl2O as oxidizers C6F5 IF2, C6F5 I Cl2 and C6F5I (OCl)2 - all thermally unstable - could be prepared and characterized.In contrast to these compounds the perfluoroaromatic carboxylates: C6F5I [O(O)C RF]2 are crystalline solids thermally stable up to 200 °C. Single crystal investigations show T-coordinated iodine with significant secondary bonding between iodine and the keto oxygens. C6F5 IO-formed by hydrolysis of C6F5IX2 - changes if stored at RT forming (C6F5)2I IO3.(C6F5)2I+ - formation is also observed when C6F5 IO is heated in inert (C6F5I, C6H6, CCl4 …), protic (H2O, CH3OH, …) and strong acidic (FSO3H …) dilution medium.C6F5IO reacts with acids, acid anhydrides and acid halides as could be shown by the preparation of C6F5 ICl2 and C6F5 ICl (NO3).Starting with C6F5 IX2 different preparative ways for (C6F5)2 I+ - compounds were successful. Principly (C6F5)2 IX - compounds decompose thermally forming C6F5I + C6F5X.C6F5 IX4 - compounds can be obtained from C6F5 IF4 which is the specific displacement product of IF5 with Si (C6F5)4. By nucleophilic displacement it is possible to prepare C6F5 IF2O, C6F5 IO2, C6F5 IO (OAcF)2 and C6F5 I [OC(CH3)2  C(CH3)2O]2,wich are all white, thermally stable solids.For the fluorine-ligand-exchange we used silycompounds as reagents. If the ligand is oxidable by C6F5 I(V) a stepwise reduction via C6F5I(III) to C6F5I could be shown by NMR-measurements.  相似文献   

15.
Treatment of RnGeCl4−n with {S(C6H3SH)2O} (1) afforded the stable phenoxathiin-4,6-dithiolate compounds [{S(C6H3S)2O}GeR2] [n = 2; R = Et (2), Ph (3)] and [{S(C6H3S)2O}GeRCl] [n = 1; R = Et (4), Ph (5)]. Treatment of GeCl4 with 1 in benzene afforded the dichloro compound [{S(C6H3S)2O}GeCl2] (8) at 7 °C. Bromo compounds [{S(C6H3S)2O}GeRBr] [R = Et (6), Ph (7)] and [{S(C6H3S)2O}GeBr2] (9) were synthesized by halogen exchange from the appropriate chloro derivative using KBr/HBr. X-ray structure determinations of diorganyl dithiolate compounds 2 and 3 revealed that germanium atom is contained in a boat–chair-shaped eight-membered central ring and displays a tetrahedral geometry. In contrast, compounds 46 display a boat–boat-shaped central ring with a significant intramolecular transannular O···Ge interaction. The geometry of the pentacoordinate Ge atom in these last complexes may be described as distorted trigonal bipyramidal with a 62–65% distortion displacement.  相似文献   

16.
Rod-like organogold(I) complexes [AuR(CNC6H4O(O)CC6H4OC10H21-p)] were prepared and their liquid crystal behaviour was studied. Depending on the nature of R, the synthetic methodology was different. Thus, for R = substituted alkynyl ligands, the new compounds were prepared in two steps:(i) reaction of [AuCl(tht)] (tht = tetrahydrothiophene) with R′CCH(R′ = C5H4N, C6H4CN, C6H4CCC5H4N) in the presence of NaOAc to give insoluble [Au(CCR′)]n; (ii) reaction of the latter polymers with the isonitrile CNC6H4O(O)CC6H4OC10H21-p.For R = fluorinated aryls, the complexes were prepared by displacement of tht from the compounds [AuR(tht)] (R = C5F4N, C6F4C5H4N, C6F5) with isonitrile.In addition, an unexpected ionic derivative [Au(CCC5H4NC10H21)2][Au(CCC5H4N)2] was formed in the reaction between [PPh4][Au(CCC5H4N)2] and C10H21I. All these compounds have been characterized by IR and NMR spectroscopy and mass spectrometry. The X-ray crystal structure of the compound with R = CCC5H4N shows a linear molecule in which the gold atom is surrounded by the pyridine-containing acetylene and the isonitrile ligand, and no direct gold-gold interaction occurs. Six of the neutral compounds are liquid crystals and their optical, thermal and thermodynamic data were analyzed and compared in terms of molecular polarizability.  相似文献   

17.
A promising approach to the unknown type of [Ar′(Ar)IF2]X salts is offered. x-FC6H4IF4 (x=2, 3, 4) reacts with C6F5BF2 in CH2Cl2 and forms [x-FC6H4(C6F5)IF2][BF4] salts in good yields. For [4-FC6H4(C6F5)IF2][BF4] the fluoro-oxidizer property is shown in reactions with weakly reducing agents like E(C6F5)3 (E=P, As, Sb, Bi) and ArI (Ar=4-FC6H4, C6F5). The fluorine/aryl substitution method is also applied to the synthesis of [(4-FC6H4)2IF2][BF4], an example with two identical aryl groups in the difluoroiodonium(V) moiety.  相似文献   

18.
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   

19.
Dithiophosphoric acids [HS2P(OC2H4CnF2n+1)2] (n = 4, 6) have been prepared in high yields. Deprotonation and reaction with transition metal substrates affords fluorous metal complexes which have been characterised by elemental analysis, mass spectrometry, IR and NMR spectroscopies. The structures of [Cu{S2P(OC2H4CnF2n+1)2}(PPh3)2] (n = 4, 6) and [Cu{-S2P(OC2H4C4F9)2}(PPh3)]2 have been determined by single crystal X-ray diffraction.  相似文献   

20.
Pentafluorophenyliodine(V) Compounds. 2. Pentafluorophenyliodine Tetrafluoride C6F5IF4: Synthesis via Fluorine-Aryl-Substitution on IF5 — Properties and Structure. Structural Analysis of the Monovalent Iodine Parent Compound C6F5I The nucleophilic fluorine-aryl substitution reaction on IF5 with pentafluorophenyl, Bi(C6F5)3, leads to C6F5IF4 in good yields and high purity. The thermal stability of C6F5IF4 and its NMR spectrometric behaviour in solution will be described. The crystal structure of C6F5IF4 will be discussed in comparison to IF5. In addition data of the molecular and crystal structure of the monovalent iodine parent compound C6F5I will be given.  相似文献   

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