Studies on fluoroalkylation and fluoroalkoxylation: 2. Perfluoroalkylation of aromatics with perfluoroalkyl iodides in the presence of copper

Perfluoroalkyl iodide R_fI [R_f = (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 (R_fC₆H₄Y). 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.     

Substitution reactions of IF5

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 IF_5?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 R_fCOOSi(CH₃)₃ (R_f = C₆F₅, 4HC₆F₄) appeared to be independent of the educts molar ratios because the only products are IF(R_fCOO)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.     

Barriers to internal rotation in 1,3,5-trineopentylbenzenes: 10—13C and 19F NMR band shape studies and force field calculations

1,3,5-Trineopentylbenzenes (TNB) with one or two benzylic substituents in each neopentyl group were synthesized. The substituents were F, Cl, Br, J, OCH₃, OCOCH₃, OSi(CH₃)₃ and CH₃ and, in cases of disubstitution, F, Cl, Br, CH₃ and Cl, CH₃ and Br and ? SCH₂CH₂S? . Barriers to internal C_sp3? C_sp2 (aryl) and C_sp3? C_sp3 rotation were estimated by ¹³C and ¹⁹F NMR band shape methods. Estimated barriers in the TNB series were found to be very close to those found for the corresponding mononeopentylbenzenes. For some of the compounds studied, molecular mechanics (MM) calculations were performed with the Allinger MMP1 program. Differences between calculated and experimental estimated barriers were found, and possible sources of these discrepancies in terms of parameters used in the MMP1 program are discussed.     

35Cl,79Br,81Br,and127I NQR spectra of HgHal2·XCH2CH2X complexes,X = OCH3, SCH3, and N(CH3)2

Conclusions From the NQR spectra of the halides HgHal₂ -D (Hal = Cl, Br, or I; D = SCH₃CH₂CH₂SCH₃, N(CH₃)₂ CH₂CH₂N(CH₃)₂, or OCH₃CH₂CH₂OCH₃) it follows that in their complexing ability the sulfur, nitrogen, and oxygen atoms can be arranged in the order: S > N > I. A structure with equivalent halogens is realized in the considered complexes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1895–1897, August, 1973.The authors consider it their duty to thank G. K. Semin for his valuable advice and interest in the work.     

Fluorinated phosphorus compounds: Part 9. The reactions of bis(fluoroalkyl) phosphorochloridates with oxygen nucleophiles

Twenty nine bis(fluoroalkyl) phosphates (R_FO)₂P(O)OR were prepared in 18-75% yield by treating phosphorochloridates (R_FO)₂P(O)Cl, where R_F 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.     

Atmospheric Chemistry of CH3CH2OCH3: Kinetics and Mechanism of Reactions with Cl Atoms and OH Radicals

The atmospheric chemistry of methyl ethyl ether, CH₃CH₂OCH₃, was examined using FT‐IR/relative‐rate methods. Hydroxyl radical and chlorine atom rate coefficients of k (CH₃CH₂OCH₃+OH) = (7.53 ± 2.86) × 10⁻¹² cm³ molecule⁻¹ s⁻¹ and k (CH₃CH₂OCH₃+Cl) = (2.35 ± 0.43) × 10⁻¹⁰ cm³ molecule⁻¹ s⁻¹ were determined (297 ± 2 K). The Cl rate coefficient determined here is 30% lower than the previous literature value. The atmospheric lifetime for CH₃CH₂OCH₃ is approximately 2 days. The chlorine atom–initiated oxidation of CH₃CH₂OCH₃ gives CH₃C(O)H (9 ± 2%), CH₃CH₂OC(O)H (29 ± 7%), CH₃OC(O)H (19 ± 7%), and CH₃C(O)OCH₃ (17 ± 7%). The IR absorption cross section for CH₃CH₂OCH₃ is (7.97 ± 0.40) × 10⁻¹⁷ cm molecule⁻¹ (1000–3100 cm⁻¹). CH₃CH₂OCH₃ has a negligible impact on the radiative forcing of climate.     

The products of the reaction of the hydroxyl radical with 2-ethoxyethyl acetate

The gas-phase reaction products of the OH radical with 2-ethoxyethyl acetate (EEA, CH₃C(O)OCH₂CH₂OCH₂CH₃) have been investigated. 1,2-Ethanediol acetate formate (EAF, CH₃C(O)OCH₂CH₂OC(O)H) and ethyl formate (EF, HC(O)OCH₂CH₃) were identified as the two main products. A third product, ethylene glycol diacetate (EGD, CH₃C(O)OCH₂CH₂OC(O)CH₃), was also observed. EAF, EF, and EGD formation yields were determined to be 0.37 ± 0.03 and 0.328 ± 0.018 and 0.040 ± 0.005, respectively. Proposed reaction mechanisms are discussed and compared with these data. © 1996 John Wiley & Sons, Inc.     

Darstellung und eigenschaften von triorganogermanium-, silicium- und -kohlenstoffsulfinsäurederivaten

A number of hitherto unknown sulfinic acid derivatives of germanium, silicon and carbon, R₃MO₂SR, were prepared by reaction of anhydrous aliphatic aromatic silver sulfinates, RSO₂Ag, with triorgano IVa element halides of the type R₃MX (R  aliphatic or aromatic group; M  Ge, Si, ;; X  Cl, Br). Their ester-like structure and the trigonal pyramidal configuration of the R₃M group result unequivocally from ¹H NMR, mass, IR and Raman spectroscopic investigations. The methyl esters (CH₃)₃MO₂SCH₃ (M  Ge, Si, C) are compared with the already known sulfinato complexes of tin and lead, (CH₃)₃SnO₂SCH₃ and (CH₃)₃PbO₂SCH₃.     

Über Chalkogenolate. 180. Methoxythiocarbonyl-methylsulfane CH3O?CS?Sx?CH3 mit x = 1, 2 und Methylthiothiocarbonyl-methylsufane CH3S?CS?Sx?CH3 mit x = 1, 2

On Chalcogenolates. 180. Methoxythiocarbonyl Methyl Sulfanes CH₃O? CS? S_x? CH₃ with x = 1, 2 and Methylthiothiocarbonyl Methyl Sulfanes CH₃S? CS? S_x? CH₃ with x = 1, 2 The monosulfanes have been prepared by known procedures. For the first time the disulfanes have been synthesized by reaction of K[S₂C? OCH₃] and K[S₂C? SCH₃] with the S-methyl ester of methanethiosulfonic acid CH₃? SO₂? SCH₃. The sulfanes CH₃O? CS? S_x? CH₃ and CH₃S? CS? S_x? CH₃, where x = 1 and 2, have been characterized by means of electron absorption, infrared, nuclear magnetic resonance, and mass spectra.     

Untersuchungen über das Reaktionsverhalten von Antimonpentachlorid. III [1]. Zur Reaktion von Antimon (V)-chlorid mit Methylisocyanat

Studies on the Reactivity of Antimony Pentachloride. III. The Reaction of Antimony(V) Chloride and Methylisocyanate Methylisocyanate CH₃NCO reacts with SbCl₅ in boiling CCl₄ by an insertion-reaction to a product of the formula C₅H₆Cl₉N₂O₂Sb I, which has the chlorformamidinium-structure (Cl? C(O)? N(CH₃)? CCl? N(CH₃)? C(O)? Cl)⊕SbCl₆?. Hydrolysis of I yields the heterocycle C₅H₆N₂O₄ II. The reaction with methanol gives (CH₃? NH? CCl? NH? CH₃)⊕SbCl₆? III and (CH₃? NH? CCl? N(CH₃)? C(O)? OCH₃)⊕SbCl₆? IV. The i.r. and Raman spectra of the compounds I, III and IV are discussed.     

Investigations on the Synthesis,Structural Characterization,and Crystal Structures of Three Diiron and Tetrairon Azadithiolate Complexes

Three diiron and tetrairon azadithiolate complexes as models for the active site of [FeFe] hydrogenase were prepared. Reaction of complex Fe₂(SCH₂OH)₂(CO)₆ and NH₂CH₂CH₂CH₂OCH₃ resulted in the diiron azadithiolate hexcarbonyl complex Fe₂[(SCH₂)₂NCH₂CH₂CH₂OCH₃](CO)₆ ( 1 ) in moderate yield. Furthermore, treatment of complex 1 with mono phosphine ligand PPh₃ and diphosphine ligand Ph₂PCH₂CH₂PPh₂ in the presence of decarbonylation reagent Me₃NO · 2H₂O yielded the phosphine‐substituted azadithiolate complexes Fe₂[(SCH₂)₂NCH₂CH₂CH₂OCH₃]CO)₅(PPh₃) ( 2 ) and {Fe₂[(SCH₂)₂NCH₂CH₂CH₂OCH₃](CO)₅}₂(Ph₂PCH₂CH₂PPh₂) ( 3 ) respectively. The new complexes 1 – 3 were fully characterized by elemental analysis, IR, ¹H, ¹³C, ³¹P NMR spectroscopy and X‐ray crystallography. It is worthy to note that the crystallographic studies show the unusual difference of the methoxypropanyl substituent on the N atom of complexes 1 and 2 , largely because of the affection of phosphine ligand PPh₃. In addition, complex 1 was found to be a catalyst for H₂ production under electrochemical condition.     

Synthesis and Crystal Structure of Tellurium(II) bis(2‐methoxycarbonylethanethiolate): A Novel Coordination Mode of Tellurium

The tellurium(II) dithiolates Te[SCH₂CH₂C(O)OCH₃]₂, ( 1 ), Te[SCH₂CH₂CH₂SC(O)CH₃]₂, ( 2 ), and Te[SCH₂CH₂CH₂CH₂SC(O)CH₃]₂, ( 3 ) were synthesized from Te(S^tBu)₂ and the corresponding thiol. All compounds are sensitive toward higher temperatures and light and decompose to elemental tellurium and the disulfide. In the solid state, the Te atom of 1 exhibits the novel Te(S₂Te₂) coordination mode. Additionally to the two Te—S bonds, each Te atom forms two long Te···Te contacts to neighboring molecules, leading to a coordination number of four and a distorted sawhorse configuration. No intramolecular Te···O interactions are present in the solid state, in accordance with ab initio calculations (MP2/ecp‐basis) for the isolated molecule. ¹²⁵Te NMR shifts of all compounds lay within a narrow range and close to the respective shift of other Te(SCH₂R)₂ compounds. VT ¹²⁵Te NMR spectra gave no hint to donor acceptor interactions in solution for any of the compounds and thus corroborate results from IR‐spectroscopy, ab initio geometry optimizations, and thermochemical calculations.     

PM3 study of the proton affinities of 2-, 3-, and 4-monosubstituted pyridines in the gas phase

Heats of formation (ΔH_f) and proton affinities (PA) of 2-, 3-, and 4-monosubstituted pyridines in the gas phase are calculated using the AM1 and PM3 semiempirical methods. The following substitutents are considered: NO₂, CN, CF₃, CHO, F, Cl, COCH₃, H, CH₃, OCH₃, SCH₃, NH₂, and N(CH₃)₂. The results are compared with the experimental data. Both methods reproduce the ΔH_f with comparble accuracy; the rms deviations are 4.1 (AM1) and 4.5 kcal/mol (PM3) for the free bases and 9.5 (AM1) and 9.7 kcal/mol (PM3) for their conjugated acids. The PA are systematically underestimated by both methods, but AM1 appears to be clearly better than PM3 for reproducing the experimental values. The rms deviations for AM1 and PM3 are 5.1 and 9.6 kcal/mol, respectively. This is due to a cancellation of systematic errors in the calculated ΔH_f in the AM1 case and to a summation of the errors in the PM3 case. Both methods correctly reproduce conformations of the molecules under consideration.     

Preparation,properties and reactivities of novel platinum compounds containing a thiomethoxymethyl group

Oxidative addition of ClCH₂SCH₃ to PtL₄ afforded trans-PtL₂(CH₂SCH₃)Cl (Ia, L = Ph₃P;Ib, L = MePh₂P). Treatment of I with NH₄PF₆ or Et₃OBF₄ in CH₂C1₂ gave ionic species, [PtL₂(CH₂SCH₃)]X (II, L = Ph₃P, MePh₂P, X = BF₄, PF₆), while similar treatment with MeSO₃F in benzene yielded a new type of stable dimethylsulfonium methylide—platinum complex, trans-[PtL₂(CH₂SMe₂)Cl] SO₃F (IIIa, L = Ph₃P; IIIb, L = MePh₂P). Action of H₂O₂ on Ia gave [Pt(Ph₃P)(μ-CH₂SCH₃)C1]₂ (IV) and its triphenylarsine analog, [Pt(Ph₃As)(μ-CH₂SCH₃)C1]₂ (V) was prepared in one step by oxidative addition of ClCH₂SCH₃ to Pt(AsPh₃)₄. The structural difference between [Pt(Ph₃P)(μ-CH₂SCH₃)C1]₂ and Pd(Ph₃P)- (CH₂SCH₃)C1 is discussed in terms of the difference in the ionization potential from d¹⁰ to d⁸ electronic state of metals.     

Complexes carbeniques des ferroporphyrines: Preparation de complexes carbeniques comportant deux substituants electrodonneurs par alcoolyse ou thionolyse des complexes halogenocarbeniques correspondants

α-Halocarbeneporphyriniron complexes, Fe(P)(C(Cl)R) react with alcohols or thiols with substitution of the chlorine atom by OR′ or SR′ groups. This reaction has been used to obtain new carbeneporphyriniron complexes in which the carbene ligand is substituted by two electrodonating groups. The complexes Fe(P)(C(XR′)R) with XR′ = OCH₃ or OC₂H₅, R = CH₃ or (CH₃)₂CH and P = TPP (tetraphenylporphyrin) or TTP (tetratolylporphyrin) and with XR′ = SCH₂C₆H₅, R = CH₃ and P = TPP or TTP, have been isolated and fully characterized.     

The reactions of a secondary phosphite with chloro- and pentan-2,4-dionato complexes of iridium(I) and rhodium(I)

The secondary phosphite $\text{OCH}{}_2\text{CMe}{}_2\text{CH}{}_2\text{OP}$(O)H reacts with chlorobis(cyclooctene) rhodium(I) dimer to give RhX(R₂POHOPR₂)₂(R₂POH) (X=H, Cl) and RhCl₂(R₂POHOPR₂)(R₂POH)₂ where R₂PO = $\text{OCH}{}_2\text{CMe}{}_2\text{CH}{}_2\text{P}$O. The iridium analogue yields corresponding products. The phosphite reacts with bis-(cyclooctene) pentan-2,4-dionatorhodium(I)to give Rh(R₂POHOPR₂)₃ and with the corresponding iridium complex to produce Ir(acac)(R₂POHOPR₂)₂. Some of the complexes act as catalysts or catalytic precursors for the stereoselective reduction of 4-t-butylcyclohexanone.     

TiCl(OCH3)(SO3Cl)(OSO2F)-chloro(chlorosulfato)(fluorosulfato)-methoxytitanium(IV) - asymmetric titanium(IV) compound

A stable titanium(IV) compound with four different kinds of ligands, TiCl(OCH₃)(SO₃Cl)? (SO₃F), results when TiCl₂(OCH₃)(SO₃F) is refluxed with HSO₃Cl using CH₂Cl₂ as the solvent. It is an off-white solid and decomposes around 125°C. The powder X-ray diffraction studies of the title compound will be discussed along with other physical and chemical properties.     

Unexpected formation of N-fluoroalkaneacyl anilides from the reactions of fluoroalkanesulfonyl azides with nitrobenzene and its derivatives

The thermal reactions of fluoroalkanesulfonyl azides R_fCF₂SO₂N₃1 with nitrobenzene and its derivatives XC₆H₄NO₂ (X=H, F, Cl, CF₃) gave the unexpected N-fluoroalkaneacyl anilides R_fCONHC₆H₄X (X=H, Cl, F, CF₃) in addition to fluoroalkanesulfonyl amides R_fCF₂SO₂NH₂. Under the same reaction conditions, however, nitrobenzene containing an electron-donating group RC₆H₄NO₂ (R=CH₃, OCH₃) reacted with 1 affording the corresponding N-fluoroalkanesulfonyl anilides R_fCF₂SO₂NHC₆H₃(NO₂)R. Other electron-poor benzene derivatives, such as benzaldehyde, benzoate, and acetophenone C₆H₅Y(Y=CHO, COCH₃, CO₂CH₃) all gave the meta-substituted N-fluoroalkanesulfonyl anilides R_fCF₂SO₂NHC₆H₄Y.     

Novel Ortho effects detected in the fast atom bombardment mass spectra of substituted bisaryl phosphate antagonists of platelet-activating factor

A series of substituted bisaryl phosphate compounds, (R¹CH₂)⁺ ArOP = O(O^?)(OArR²R₃), was analyzed and characterized by fast atom bombardment mass spectrometry. Abundant fragment ions were observed and correlated with the proposed structures. From fragmentation pattersn, ‘ortho effect’ reactions were demonstrated to have occurred when the phosphoryl oxygen reacted with the (CH₂R¹)⁺ and C?O(OCH₃) substituents in the ortho position, relative to the phosphate group, and displaced the R¹ and OCH₃ groups, respectively, to produce phosphorus containing six-membered rings fused to the aryl moiety. When the (CH₂R¹)⁺ substituents were in the meta position relative to the phosphate group, the ‘ortho effect’ reactions were not observed. However, when the C?O(OCH₃) substituent was in the meta position relative to the phosphate group, an abundant fragment ion containing a five-membered phosphate ring fused to the aryl ring was detected with the original phosphoryl oxygen ortho to both the phosphate oxygen and a formyl group, formed from the original C?O(OCH₃) substituent. All other fragmentations not involving the ‘ortho effect’ reactions were nearly identical for the different structural isomers of the substituted bisaryl phosphate compounds.     

Formation and photochemistry of organic sulfur compound–chlorine atom complexes

Photochemical reactions of organic sulfur compounds (CH₃SCH₃, C₂H₅SCH₃ and C₂H₅SC₂H₅)–chlorine atom complexes have been studied using a combined pulse radiolysis-laser flash photolysis technique. Excitation of all complexes has resulted in photobleaching with a similar quantum yield (0.37±0.07), independent of solvent polarities and concentration of solutes. The results were compared with previous studies of the analogous dimethyl sulfoxide (DMSO)–Cl complexes. It is concluded that the significant change of photobleaching quantum yields of the excited DMSO–Cl complex observed in the DMSO-CCl₄ mixed solvent is mainly due to the specific solvation effect of DMSO for cations.