Novel synthesis of unusual classes of fluorocarbon organosulfur compounds using elemental fluorine as a reagent (original) (raw)
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Inorg Chem, 1986
Reaction of H2C(S02CF3)2 with (Ph3P),RuH2 in neat arene solvents produces (a-arene)RuH(PPh3).zf-HC(SO2CF&-. The lH NMR spectra of these compounds indicate that substituents on the arene ring stabilize one of several ring rotational conformations. Molecular orbital calculations at the extended Huckel level were utilized to explore the structural distortion of the RuH(PPh&+ units in these compounds as well as the dynamics of rotation about the arene-Ru axis. Computations on (arene)RuH(PH&+ (arene = benzene, aniline, phenylborane) each showed similar distortions in the tripod portion of the molecule which can be traced to more efficient donation of electron density from the hydride to the metal compared to the phosphine ligands. The structure for each of these model compounds was optimized, and barriers to rotation about the arene-Ru bond were computed. Crystal structure determinations on (r-PhCHJ-
Inorganic Chemistry, 1986
Me2NCN)(SN)2, generated in situ from 2a. To test this possibility we added a solution of 2a in CC14 to a green solution of (NSCl)3 in CC14 at 60 0C.29 However, this reaction resulted in the dechlorination of (NSC1)3 by 2a to give S4N4 and la. An alternative mechanism for the production of 3a involves the formation of the monosubstituted derivative of la, (Me,NCN)(NSCl)(NSNSO), which undergoes intermolecular elimination of SO2 to give RN=S=NR (where R = (Me2NCN)(NSCl)(NS)). When R = (Ph2PN)2(SN), this type of compound readily undergoes a six-to eight-membered-ring expansion to give a spirocyclic compound, which forms a monocyclic eight-membered ring on thermal decomposition.M A similar sequence of transformations could account for the formation of h3'
Journal of Fluorine Chemistry, 1999
The synthesis of the new halogenated alcohol BrCF 2 CFClCH 2 CHICH 2 OH as a precursor of 4,5,5 tri¯uoro-4-ene pentanol F 2 C=CFC 3 H 6 OH is based on a two-step process. First, the radical addition of iodine monobromide to chlorotri¯uoroethylene (CTFE) led to the expected BrCF 2 CFClI (I) and ICF 2 CFClBr (II), but also to BrCF 2 CFClBr (III) and ICF 2 CFClI (IV), the amount of which determined by 19 F NMR depended on the reaction conditions: by feeding CTFE into IBr continuously or in batches; photochemical or thermal initiations, and with various initial [IBr] 0 /[CTFE] 0 molar ratios. In most cases, isomer (I) was mainly produced. The second step concerned the addition of such a mixture to allyl alcohol yielding the polyhalogenoalcohol with a quantitative conversion of (I). The reactivity of different halogeno end-groups of these isomers toward the allyl alcohol was discussed. Reduction of the iodine atom into hydrogen and the halogenated alcohol was accompanied by that of the bromine atom leading to BrCF 2 CFClC 3 H 6 OH and HCF 2 CFClC 3 H 6 OH (V). Dehalogenation of the former alcohol in the presence of zinc led to F 2 C=CFC 3 H 6 OH while dehydrochlorination of (V) into tri¯uorovinyl hydroxy monomers was achieved in the presence of potassium hydroxide but in poor yields. Strategies starting from the radical additions of iodine monochloride and of iodine monobromide were compared showing that the former led to better overall yields of tri¯uorovinyl alcohol than the latter. # 0022-1139/99/$ ± see front matter # 1999 Elsevier Science S.A. All rights reserved. P I I : S 0 0 2 2 -1 1 3 9 ( 9 8 ) 0 0 2 8 0 -2 4.5.1. 4-Chloro-4,5,5-trifluoropentanol (IY b H ) 1 H NMR (CDCl 3 ) : 1.90(qi, 3 J HH 6.2 Hz, CH 2 CH 2 OH, 2H); 2.23(m, CFClCH 2 , 2H); 2.75 (broad singlet, shifted with dilution or in the presence of Cl 3 CNCO); 3.68 (t, shifted to 4.50 ppm in the presence of Cl 3 CNCO, 3 J HH 6.6 Hz, CH 2 OH, 2H); 5.81 (td, 2 J HF 54.8 Hz, 3 J HF 3.2 Hz, HCF 2 , 1H). F NMR (CDCl 3 ) : À125.33(tddd, X part of an ABX system, 3 J FcH 10.4 Hz, 3 J FcFa 10.7 Hz, 3 J FcFb 9.7 Hz, 3 J FcH 3.3 Hz, CF c Cl, 1F); À130.30 (AB part, Fa À129.35, 2 J FaFb 284.4 Hz, 3 J FaFc 10.6 Hz, 2 J FaH 55.0 Hz, Fb À131.28, 2 J FbFa 283.7 Hz, 3 J FbFc 9.9 Hz, 2 J FbH 55.0 Hz) 16.5 g (0.064 mol) of a second pure fraction was distilled (colourless liquid) Bp, 90±928C/21 mm Hg (yield49.6%). (dddt, 3 J HF 22.5 Hz, 4 J HF 2.4 Hz, 4 J HF 4.0 Hz, 3 J HH 6.8 Hz, CFCH 2 , 2H); 3.15 (broad singlet, shifted with dilution or with Cl 3 CNCO, OH, 1H); 3.66 (t, shifted to 4.40 ppm with Cl 3 CNCO, 3 J HH 6.3 Hz, CH 2 OH). F NMR (CDCl 3 ) : À106.1 (ddt, 2 J FFgem 88.4 Hz, 3 J FF 32.0 Hz, 4 J FH 2.5 Hz); À125.2(ddt, 2 J FF 88.4 Hz, 3 J FF 113.6 Hz, 4 J FH 3.9); À174.6(ddt, 3 J FF 32.0 Hz, 3 J FF 113.6 Hz, 3 J FH 22.5 Hz). 13 C NMR (CDCl 3 ) : 21.9(dd, 2 J CF 22.4 Hz, 3 J CF 2.2 Hz, CFCH 2 ); 28.2 (d, 3 J CF 2.3 Hz, CH 2 CH 2 OH); 61.2 (s, CH 2 OH); 128.5 (ddd, 1
Helvetica Chimica Acta, 2006
Si(C 6 F 5) was used for the preparation of a series of perfluorinated, pentafluorophenyl-substituted 3,6-dihydro-2H-1,4-oxazines (2-8), which, otherwise, would be very difficult to synthesize. Multiple pentafluorophenylation occurred not only on the heterocyclic ring of the starting compound 1 (Scheme), but also in para position of the introduced C 6 F 5 substituent(s) leading to compounds with one to three nonafluorobiphenyl (C 12 F 9) substituents. While the tris(pentafluorophenyl)-substituted compound 3 could be isolated as the sole product by stoichiometric control of the reagent, the higher-substituted compounds 5-8 could only be obtained as mixtures. The structures of the oligo(perfluoroaryl) compounds were confirmed by 19 F-and 13 C-NMR, MS, and/or X-ray crystallography. DFT simulations of the 19 F-and 13 C-NMR chemical shifts were performed at the B3LYP-GIAO/6-31++G(d,p) level for geometries optimized by the B3LYP/6-31G(d) level, a technique that proved to be very useful to accomplish full NMR assignment of these complex products.
Organometallic Fluorides: Compounds Containing Carbon−Metal−Fluorine Fragments of d-Block Metals
Chemical Reviews, 1997
by group number with comprehensive reference to the original literature. Within each group the metals are listed in decreasing oxidation state. For each subsection of sections IV-X, the topics have been arranged in the following sequence; synthesis, characterization, fluoro-chloro, fluoro-oxo, fluoro-nitro, fluoro-alkyl compounds, complexes of weakly coordinated fluorinated anions, and recent reports of C-F bond activation. Slight variations will necessarily be found for example where uses of the fluorides in synthesis and catalysis are included. In the final section, conclusions regarding the reactivity patterns exhibited by organometallic fluorides in comparison with the heavier halides are made. Tables 12 and 13 represent an up to date summary of terminal and bridging M-F bond distance ranges, and also related bond distances in complexes of weakly coordinating anions. Organometallic fluorides have found novel applications in both synthesis and catalysis, and these are summarized in Table 14. Ligands such as the bulky teflate group (OTeF 5-), having electronegativity values comparable with that of fluorine, are considered pseudofluorides. 8,9 Pseudofluorides are now well-established as ligands in main group and high oxidation state transition metal chemistry and are not dealt with here. Carbonfluorine-metal bridges are relatively uncommon in organometallic systems and are only briefly mentioned with some examples. A selective representation of such "organometallic fluorides" includes Ru-(SC 6 F 4-µ-F)(SC 6 F 5)(PPhMe 2), 10 {2,4,6-(CF 3) 3 C 6 H 2 }Li, 11 [Cp*ThMe][B(C 6 F 5) 4 ], 12 Cp(acac)Zr(µ-Cp)B(C 6 F 5) 3 , 13 and Cp* 2 ZrOB(C 6 F 5) 3. 14 In these compounds one perfluoro group orients itself so that a fluorine approaches the metal. This contact is typically longer than any metal-fluorine bond distance. The associated C-F bond is lengthened (∼0.05 Å) over the average of the remaining C-F bond distances. This is consistent with C-F-M bridge formation. Very often low-temperature 19 F NMR spectroscopy confirms the static structure established in the solid state.