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1.
Using PTC or cosolvent, both perfluoroalkyl bromides such as Br (CF2)2O(CF2)2SO2Na ( 1 ), Br(CF2)2OCF2CO2H ( 2 ), Cl(CF2)4Br ( 3 ), Cl(CF2Br ( 4 ), n-C6F13Br ( 5 ), n-C8F17Br ( 6 ), H(CF2)8Br ( 7 ), α, ω-dibromides O(CF2CF2Br)2 ( 8 ), Br(CF2)6Br ( 9 ) and Br(CF2)8Br ( 10 ) reacted readily with Na2S2O4 in the presence of NaHCO3 in aqueous solution to form the corresponding perfluoroalkane sulfinates NaO2S(CF2)2O(CF2)2SO2Na ( 11 ), NaO2S(CF2)2OCF2CO2Na ( 12 ), Cl(CF2)4SO2Na ( 13 ), Cl(CF2)2SO2Na ( 14 ), n-C3F13SO2Na ( 15 ), n-C8F17SO2Na ( 16 ), H(CF2)8SO2Na ( 17 ), α, ω-disulfinates O(CF2CF2SO2Na)2 ( 18 ), NaO2S(CF2)4SO2Na ( 19 ) and NaO2S(CF2)8SO2Na ( 20 ) in 66—97% yields. To this new and general reaction of perfluoroalkyl bromides, the name sulfinatodebromination is proposed.  相似文献   

2.
Using acetonitrile or DMF as cosolvent, both perfluoroalkyl iodides such as Cl(CF2)nI (n = 4,6,8, la—lc ), CF3 (CF2)n I (n = 5,6,7, ld—lf ), I (CF2)n O (CF2) SO3 Na(n = 2,4,6, lg—li ) and perfluoroalkyl bromides such as Cl (CF2)n Br (n = 4,6, 3a—3b ) and C7F15 Br (3e) reacted with Rongalite in aqueous solution to give the corresponding sulfinates Cl (CF2)n SO2 Na (n = 4,6,8, 2a—2c ), CF3-(CF2)nSO2Na (n = 5,6,7, 2d—2f ) and NaO2S(CF2)nO(CF2)2SO3Na (n = 2,4,6, 2g—2i ) in moderate yields. 1 H-perfluoroalkanes were formed as the main products when other solvents such as ethanol. iso-propanol, 1,4-dioxane and morpholine were used.  相似文献   

3.
Several derivatives of secondary perfluoroalkyl iodides such as CF3CFI(CF2)2O(CF2)3SO2F (3), CF3CFI(CF2),O(CF2)2SO3Na (4), CF3CFI(CF3)n Cl (n=2, 7a; n=4, 7b) and CF3(CF2)2-OCFICF3 (8) were synthesized using known methods, their reaction with sodium dithionite was studied and various olefins were added into the reaction system as radical traps to yield the 1:1 radical adducts.  相似文献   

4.
Sodium perfluoroalkanesulfinate, RFSO2Na [RF?Cl(CF2)4, 1a; CF3(CF2)5, 1b; Cl(CF3)6, 1c] reacted with bromine in aqueous solution to give the corresponding sulfonyl bromide RFSO2Br (2a-2c) and in acetonitrile or acetic acid, to form perfluoroalkyl bromide RFBr (3a-3c). Heating in acetonitrile at 80°C, 2a-2c were converted smoothly into 3a-3c. However, reaction of sodium α,α-dichloropolyfluoroalkanesulfinate RCCl2SO2Na (R?CF3, Cl(CF2)n, n=2, 4, 6, 5a-5d) with bromine in aqueous solution gave directly the corresponding bromoalkanes 1-bromo-1,1-dichloropolyfluoroalkane RCCl2Br (6a-6d). In aqueous potassium iodide solution, 1a-1c, 5a and 5b also reacted with iodine to form the corresponding iodo-polyfluoroalkane 4a-4c, 7a and 7b directly. 6a and 7a underwent free radical addition to alkene readily in the presence of free radical initiator and reacted with Na2S2O4 in the usual way to form α,α-dichloropolyfluoroethane sulfinate (5a). 5a was stable in strong acid, but reacted with strong base to yield 10. 5a was oxidised by hydrogen peroxide to the sulfonate 11 and reduced by zinc in dilute acid to from the α-chloro sulfinate 12.  相似文献   

5.
Polyfluoroalkyl iodides, such as Cl(CF2)nI(n=4, 6, 8, 1b-1d) and F(CF2)nI (n=6, 8,1e-1f) reacted with sodium sulfite in neutral aqueous DMF solution to give the corresponding sulfinates Cl(CF2)nSO2Na (n=4, 6, 8, 2b-2d) and F(CF2)nSO2Na (n=6, 8, 2e-2f) in moderate yields. I(CF2)2O(CF2)2SO2F ( la ) reacted under the same condition to give 3-oxa-octafluoropentane-1,5-disulfinates (2a).  相似文献   

6.
Sodium perfluoroalkanesulfinates [Cl (CF2)n SO2 Na (1), a , n = 4; b , n = 6; c , n = 8] with the reduction potentials about 0.95—1.00V could be oxidized readily with various oxidizing agents such as Mn (OAc)3 2H2O, Ce (SO4)2, HgSO4 and Co2O3 to generate perfluoroalkyl radicals which added to the olefins RCH ? CHR' to give two kinds of adducts, namely RCH (Rf) CHXR' (3, X ? H; 4, X ? OAc), with good yields depending upon the solvent system used. Different oxidizing agents showed slight variation on the yields of the adducts. The reaction time could be greatly shortened at higher temperature. Thus, this reaction provides a new way for introducing a perfluoroalkyl group into olefinic compounds.  相似文献   

7.
Sodium perfluoroalkanesulfinates [RfSO2Na(1), Rf = Cl (CF2)n; a, n = 4; b, n = 6; c, n = 8] on oxidation with various single electron oxidizing agents, such as Mn (OAc)3 · 2H2O and Ce (SO4)2, yielded perfluoroalkyl radicals capable of perfluoroalkylating aromatic compounds to give a mixture of o-and p-monoperfluoroalkylated products. Thus, this reaction provides a new method for the synthesis of o-and p-monoperfluoroalkyl substituted aromatic compounds.  相似文献   

8.
Perfluoroalkyl iodide RfI [Rf = (CF2)nO(CF2)2SO2F, n = 2, (a); n = 4, (b); (CF2)4Cl, (c)] reacted with substituted benzene C6H5Y (Y = alkyl, OCH3, CF3, F, Cl, Br, I) in the presence of copper in acetic anhydride to give the corresponding mixture of isomeric disubstituted benzene (RfC6H4Y). The conversion and yield depend on both the amount of copper used and nature of substituent. The likely explanation is that the reaction may involve a free radical process. The perfluoroalkyl radical can be trapped by cyclohexene, isopropylbenzene and styrene. Using DMSO in place of acetic anhydride as a solvent the reaction takes a different course, it is believed that the reaction in DMSO proceeds through a perfluoroalkylcopper intermediate.  相似文献   

9.
The complexes [RhCl(3−n)(MeCN)n(CF3triphos)](CF3SO3)n (n=1, 2; CF3triphos=MeC[CH2P(m‐CF3C6H4)2]3) and [M(MeCN)3 (CF3triphos)](CF3SO3)n (M=Ru, n=2; M=Ir, n=3) are catalyst precursors for some typical acetalization and transacetalization reactions. The activity of these complexes is higher than those of the corresponding species containing the parent ligand MeC[CH2P(C6H5)2]3(Htriphos). Also the complexes [MCl3(tripod)] (tripod=Htriphos and CF3triphos) are active catalysts for the above reactions. The complex [RhCl2(MeCN)(CF3triphos)](CF3SO3) catalyzes the acetalization of benzophenone.  相似文献   

10.
The synthesis and physico-chemical characterization of 1,1,2,2-tetrakis(perfluoroalkyl-methylene)ethane {[F(CF2)nCH2]2CH}2 (n=6, TK6; n=8, TK8) are reported. The synthesis consists of four steps: (1) addition of allyl alcohol to a perfluoroalkyl iodide, F(CF2)nI (n=6,8) to give the corresponding iodo-adduct; (2) dehalogenation of the adduct by treatment with zinc in aqueous acetic acid, yielding 3-perfluoro-n-alkyl-1-propene; (3) addition of 3-perfluoro-n-alkyl-l-propene to perfluoroalkyl iodide, F(CF2)nI (n=6,8) to give 1,3-perfluoro-n-alkyl-2-iodo-propane; (4) coupling of 1,3-perfluoro-n-alkyl-2-iodo-propane by zinc in acetic anhydride giving the final products. TK6 and TK8 are characterized by very low surface tension values and exhibit very good properties as potential ski-waxes.  相似文献   

11.
Complexes of trifluoromethanesulfonates (triflates) with alkali metals Na, Rb, Cs have been prepared in the presence of various macrocyclic polyether crowns [(12‐crown‐4), (15‐crown‐5) and (18‐crown‐6)]. Depending on the combination of alkali ion with crown, the complexes include separated ion pairs [Na(12‐crown‐4)2] [SO3CF3] ( 1 ) and contact ion pairs [Na(15‐crown‐5)] [SO3CF3] ( 2 ), [Rb(18‐crown‐6)] [SO3CF3] ( 3 ), and [Cs(18‐crown‐6)] [SO3CF3] ( 4 ), in which the triflate acts as a bidentate ligand. It is shown that the choice of crown ether is of paramount importance in determining the solid‐state structural outcome. The complex resulting from the pairing of crown ether ( 1 ) develops, when the crown ether is too small in relation to the alkali ion radius. When the cavity size of the crown ether is matched with the alkali ion radius, simple monomeric structures are identified in 2 , 3 and 4 . The title compounds crystallize in the monoclinic crystal system: 1 : space group P2/c with a = 9.942(3), b = 11.014(2), c = 10.801(3) Å, β = 97.30(2)°, V = 1173.1(4) Å3, Z = 2, R1 = 0.0812, wR2 = 0.1133: 2 : space group P21/m with a = 7.949(2), b = 12.063(3), c = 9.094(2) Å, β = 105.98(2)°, V = 838.3(4) Å3, Z = 2, R1 = 0.0869, wR2 = 0.1035: 3 : space group P21/c with a = 12.847(5), b = 8.448(2), c = 22.272(6) Å, β = 122.90(3)°, V = 2029.5(1) Å3, Z = 4, R1 = 0.0684, wR2 = 0.1044: 4 : space group P21/n with a = 12.871(3), b = 8.359(1), c = 19.019(4) Å, β = 92.61(2)°, V = 2044.2(6) Å3, Z = 4, R1 = 0.0621, wR2 = 0.0979.  相似文献   

12.
Products of photochemical reactions occurring in gaseous mixtures of C2F4 and CF3I under vacuum-UV irradiation were studied. The major photolysis products are linear perfluoroparaffins C n F2n+2 and linear perfluoroalkyl iodides C n F2n+2I. The product ratio is consistent with the suggested kinetic scheme of chain reactions of telomers.  相似文献   

13.
The sulfinatodeiodination reagent Ce4+ ?NaHSO3 was shown to be able to initiate the addition of perfluoroalkyl iodides to olefins at 50—70°C to give the corresponding adducts in good yield. Similarly, SO2? generated from Fe3+?NaHSO3 system can also initiate the same addition although the reagent is not able to cause sulfinatodeiodination. Furthermore it was shown that sodium perfluoroalkanesulfinate is able to initiate the same addition and there is no exchange between the perfluoroalkyl groups of R'FSO2Na and RFI.  相似文献   

14.
Hexakis(N—allylthiourea)tetracopper(I) Tetratrifluoromethanesulfonate, [Cu4{CH2=CHCH2NHC(S)NH2}6](CF3SO3)4 (sp.gr.P21/n, a = 13.5463(8), b = 24.129(2), c = 19.128(1)Å, β = 108.053(6)°, Z = 4, R = 0.0440 for 13548 unique reflections) was obtained by reduction of Cu(CF3SO3)2 with excess of N—allylthiocarbamide in benzene medium. Four crystallographical independent Cu atoms possess trigonal environment of three S atoms of CH2=CHCH2NHC(S)NH2 moiety and form Cu4S64+ adamantane—like fragments. The latteres are connected with CF3SO3 anions via (C)—H···F hydrogen bonds.  相似文献   

15.
The reaction of Na2[Fe(CO)4] with Br2CF2 in n‐pentane generates a mixture of the compounds (CO)3Fe(μ‐CO)3–n(μ‐CF2)nFe(CO)3 ( 2 , n = 2; 3 , n = 1) in low yields with 3 as the main product. 3 is obtained free from 2 by reacting Br2CF2 with Na2[Fe2(CO)8]. The non‐isolable monomeric complex (CO)4Fe=CF2 ( 1 ) can probably considered as the precursor for 2 . 3 reacts with PPh3 with replacement of two CO ligands to form Fe2(CO)6(μ‐CF2)(PPh3)2 ( 4 ). The complexes 2 – 4 were characterized by single crystal X‐ray diffraction. While the structure of 2 is strictly similar to that of Fe2(CO)9, the structure of 3 can better be described as a resulting from superposition of the two enantiomers 3 a and 3 b with two semibridging CO groups. Quantum chemical DFT calculations for the series (CO)3Fe(μCO)3–n(μ‐CF2)nFe(CO)3 (n = 0, 1, 2, 3) as well as for the corresponding (μ‐CH2) derivatives indicate that the progressively larger σ donor and π acceptor properties for the bridging ligands, in the order CO < CF2 < CH2, favor a stronger Fe–Fe bond.  相似文献   

16.
Enantiomerically pure triflones R1CH(R2)SO2CF3 have been synthesized starting from the corresponding chiral alcohols via thiols and trifluoromethylsulfanes. Key steps of the syntheses of the sulfanes are the photochemical trifluoromethylation of the thiols with CF3Hal (Hal=halide) or substitution of alkoxyphosphinediamines with CF3SSCF3. The deprotonation of RCH(Me)SO2CF3 (R=CH2Ph, iHex) with nBuLi with the formation of salts [RC(Me)? SO2CF3]Li and their electrophilic capture both occurred with high enantioselectivities. Displacement of the SO2CF3 group of (S)‐MeOCH2C(Me)(CH2Ph)SO2CF3 (95 % ee) by an ethyl group through the reaction with AlEt3 gave alkane MeOCH2C(Me)(CH2Ph)Et of 96 % ee. Racemization of salts [R1C(R2)SO2CF3]Li follows first‐order kinetics and is mainly an enthalpic process with small negative activation entropy as revealed by polarimetry and dynamic NMR (DNMR) spectroscopy. This is in accordance with a Cα? S bond rotation as the rate‐determining step. Lithium α‐(S)‐trifluoromethyl‐ and α‐(S)‐nonafluorobutylsulfonyl carbanion salts have a much higher racemization barrier than the corresponding α‐(S)‐tert‐butylsulfonyl carbanion salts. Whereas [PhCH2C(Me)SO2tBu]Li/DMPU (DMPU = dimethylpropylurea) has a half‐life of racemization at ?105 °C of 2.4 h, that of [PhCH2C(Me)SO2CF3]Li at ?78 °C is 30 d. DNMR spectroscopy of amides (PhCH2)2NSO2CF3 and (PhCH2)N(Ph)SO2CF3 gave N? S rotational barriers that seem to be distinctly higher than those of nonfluorinated sulfonamides. NMR spectroscopy of [PhCH2C(Ph)SO2R]M (M=Li, K, NBu4; R=CF3, tBu) shows for both salts a confinement of the negative charge mainly to the Cα atom and a significant benzylic stabilization that is weaker in the trifluoromethylsulfonyl carbanion. According to crystal structure analyses, the carbanions of salts {[PhCH2C(Ph)SO2CF3]Li? L }2 ( L =2 THF, tetramethylethylenediamine (TMEDA)) and [PhCH2C(Ph)SO2CF3]NBu4 have the typical chiral Cα? S conformation of α‐sulfonyl carbanions, planar Cα atoms, and short Cα? S bonds. Ab initio calculations of [MeC(Ph)SO2tBu]? and [MeC(Ph)SO2CF3]? showed for the fluorinated carbanion stronger nC→σ* and nO→σ* interactions and a weaker benzylic stabilization. According to natural bond orbital (NBO) calculations of [R1C(R2)SO2R]? (R=tBu, CF3) the nC→σ*S? R interaction is much stronger for R=CF3. Ab initio calculations gave for [MeC(Ph)SO2tBu]Li ? 2 Me2O an O,Li,Cα contact ion pair (CIP) and for [MeC(Ph)SO2CF3]Li ? 2 Me2O an O,Li,O CIP. According to cryoscopy, [PhCH2C(Ph)SO2CF3]Li, [iHexC(Me)SO2CF3]Li, and [PhCH2C(Ph)SO2CF3]NBu4 predominantly form monomers in tetrahydrofuran (THF) at ?108 °C. The NMR spectroscopic data of salts [R1(R2)SO2R3]Li (R3=tBu, CF3) indicate that the dominating monomeric CIPs are devoid of Cα? Li bonds.  相似文献   

17.
X(CF2CF2)nOCF2CF2SO2F (X=I, Br, Cl; n=1, 2, 3, 4) are widely used fluoroalkylation reagents, which can incorporate ‘heavy’ fluorous tags into organic compounds. X(CF2CF2)nOCF2CF2SO2F have both sulfonyl and halo groups. They behave as bi-functional fluoroalkylation reagents. The cleavage of the C–I bonds of I(CF2CF2)nOCF2CF2SO2F by reductants (such as Na2S2O4, Zn), single electron transfer reagents and radical initiator systems (like Bz2O2, AIBN, and (t-BuO)2, or under UV and heat) gives, respectively, the sulfinatodehalogenated products, the hydrodehalogenated products, the homo-coupling products and the perfluoroalkylated products (if alkenes, alkynes or arenes were added). The functionalization of the sulfonyl groups (SO2F) of X(CF2CF2)nOCF2CF2SO2F by esterification, amidation, and fluorination affords the corresponding perfluoroalkanesulfonates, fluoroalkanesulfonamide, and perfluoroalkanes. In many cases, both the halo and sulfonyl groups of X(CF2CF2)nOCF2CF2SO2F are transformed. These transformations finally lead to hundreds of useful highly fluorinated materials, such as supper acids, catalysts, surfactants, ion-exchange resins, electrolytes, polymers, and dense ionic liquids. Furthermore, X(CF2CF2)nOCF2CF2SO2F have commendable advantages, such as the easy preparation, the wide range of substrate tolerance, the mild reaction condition, and the high yields of desired products, which make them very promising. This review briefly summarizes the synthesis, reactivity, and applications of these intriguing reagents.  相似文献   

18.
Perfluoromethyl-Element-Ligands. XVII. Formation of Adducts of MenE(CF3)3?n Ligands with BX3 Compounds (Me = CH3; E = P, As, Sb; n = 0–3; X = H, CH3, Hal) The ligands MenE(CF3)3?n (Me = CH3; E = P, As, Sb; n = 0–3) have been prepared (partly using new methods) and studied by n.m.r. spectroscopy (1H, 19F, 31P, 13C). In order to deduce their relative donor strength their reactions with the Lewis acids “BH3”, BMe3, BMe3, Me2BBr, and BX3 (X = F, Cl, Br) have been studied. Control of adduct formation occurs by n.m.r. spectroscopy (1H, 19F). The following series of decreasing basicity or acidity are obtained:   相似文献   

19.
Halogenation of the potassium or silver salts of bis((trifluoromethyl)sulfonyl)methane(CF3SO2)2CH2 and its cyclo analogues (CF2)nSO2‐CH2SO2CF2 with N‐fluoro‐bis((trifluoromethyl)sul‐fonyl)imine (CF3SO2)2NF, chlorine or bromine gave good yields of the corresponding α‐halo disulfones (CF3SO2)2CHX and (CF2)nSO2CHXSO2CF2 (X: F, Cl, Br; n = 1,2). Some chemical transformations of these fluorinated α‐halo‐disulfones are described. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 147–151, 1999  相似文献   

20.
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   

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