Carbon-13 NMR spectra of some polychloro hydrocarbons and related compounds

Data derived from the carbon-13 NMR spectra of 37 organic polychloro compounds allow one to identify readily the ? CHCl₂, ? CCl₂? and ? CH₂Cl groups, the ¹³C signals of which are registered in the shift ranges of 67 to 78 (80), 85 to 96 and 38 to 55 (59) ppm (from TMS), respectively, and have the distinctive one bond spin-spin coupling constants ¹J(C? H) 170 to 184 Hz (for the ? CHCl₂ groups) and 147 to 158 Hz (for the ? CH₂Cl groups). The ? CCl₂CH₂CH₂Cl fragment features characteristic diamagnetic shieldings of the ? CCl₂? and ? CH₂Cl that may be related to increased electron density on both of these groups.     

Reaction of α,α,ω-trichloroalkenes with 1,1,1-trichloroethane and 1,1,1,3-tetrachloropropane,accompanied by rearrangement of radicals

Conclusions In the reaction of CCl₃CH₃ with CCl₂=CHCH₂CH₂CH₂Cl, and of CCl₃CH₂CH₂Cl with CCl₂= CHCH₂Cl, initiated by Fe(CO)₅+DMF, the main addition products are respectively compounds of structure HCCl₂CH(CCl₂CH₃)CH₂CH₂CHCl₂ and HCCl₂CH(CCl₂CH₂CHCl₂)CH₂C1. The formation of these compounds was explained by the isomeriza'tion of the radical-adducts CCl₂CH(CCl₂CH₃)CH₂CH₂CH₂Cl and CCl₂CH(CCl₂CH₂CH₂Cl)CH₂Cl, with migration of a hydrogen atom from the CH₂Cl groups found in the 5 position to the radical center.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1857–1861, August, 1980.     

Molecular structure of trichlorophosphazo compounds from ab initio calculation and chlorine-35 NQR spectroscopy data

The molecular structures of trichlorophosphazo compounds Cl₃P=NR with R = C(CH₃)₃, C(C₂H₅)₃, C(CF₃)₃, CCl(CF₃)₂, CCl₂CF₃, CCl₃, CCl₂CCl₃, and CCl(CCl₃)₂ were analyzed by combined consideration of the results of ab initio MP2/6-31G* calculations and previously measured ³⁵Cl NQR frequencies. The conformational peculiarity of these molecules caused by the relative spatial orientations of the P-Cl and N-C bonds is reflected in the calculated geometric parameters of the Cl₃P=NC fragments and in the pattern of ³⁵Cl quadrupole resonance spectra for PCl₃ groups. For these atomic groups, the ³⁵Cl NQR frequencies were brought in correlation with the charges of the chlorine atoms found by quantum-chemical calculations.     

Synthesis of block cotelomers involving a perfluorinated chain and a hydrophilic chain. III. Synthesis and use of fluorinated telogens with a trichloromethyl end group

The addition by redox catalysis (CuCl or FeCl₃ with benzoin) of CCl₄ and CCl₃? CF₂? CCl₃ on pentafluorostyrene and on fluorinated allyl ether, C₆F₁₃? C₂H₄? O? CH₂? CH?CH₂ was performed. The monoaddition compounds were mainly obtained with satisfactory yields and characterized by NMR (¹³C, ¹H, and ¹⁹F). These compounds were then used as telogens in telomerization by redox catalysis of acrylamide, methyl methacrylate, and acrylic acid and in radical-initiated telomerization of N-vinyl-pyrrolidone. The chain lengths of the hydrocarbonated sequences were determined from fluorine elemental analysis. A critical investigation of correlations between DP _n and concentrations of products involved was made.     

1H, 13C and 29Si NMR study of α- and β-silylstyrenes and their adducts with dichlorocarbene

¹H, ¹³C and ²⁹Si NMR spectra for the α- and β-silylstyrenes (E)-PhCHCHSiR₃ (I) and PhC(SiR₃)CH₂ (II) (R = Cl, Me, Ph), and those for some dichlorocarbene adducts of I and II (R = Me, Ph), were examined. From the ¹³C NMR data, the phenyl substituent in the molecules I and II enhances the electronic effects of the organosilicon substituent at Cα, and weakens these effects on the C_α resonance. The degree to which polarization of the vinyl CC bond is polarized increases with increased electron-withdrawing properties of substituent R in the SiR₃ group in compounds I and II, and correlates with the reduced reactivity of the bond toward electrophilic dichlorocarbene. Several long-range coupling constants (CC) in the molecules I, II and in their adducts with :CCl₂ were measured. The estimated CC is a useful aid for the study of electronic effects in organosilicon compounds.     

Synthese de polysiloxanes fluores. Partie IV. Obtention de disiloxanes fluores

New disiloxanes containing aromatic or aliphatic fluorinated groups are prepared and identified. The general formula of these compounds is: R_F-Q-CH₂-CH₂-Si(CH₃)₂-O-Si(CH₃)₂-CH₂-CH₂-Q′-R′_F · R_F and R′_F are halogenated groups such as C₆F₅-, C_nF_2n+1-, Cl(CFCl-CF₂)_n, CF₃-CFH-CF₂-, CF₃-, or CCl₃-. In most cases, Q or Q′ is an oxygen atom. Symmetrical disiloxanes are obtained by hydrolysis of corresponding fluorinated monochlorodimethylsilanes, and the asymmetrical ones are prepared in two steps by reacting the fluorinated olefins H₂C = CH-Q-R_F and H₂C = CH-Q′-R′_F with dihydrotetramethylsiloxane. The structures of these various compounds are elucidated by ¹H-, ¹³C- NMR and IR spectroscopy     

Radical telomerization of 3,3,3-trifluoro-1-propene with carbon tetrachloride

Telomerization of 3,3,3-trifluoropropene with CCl₄ was carried out in the presence of Fe(CO)₅ in combination with dimethylformamide (DMF) or hexamethylphoshoric triamide (HMPA) with formation of the telomers CCl₃(CH₂CHCF₃)_nCl, n=1–3, as the main products. Chromatography-mass spectrometry showed the presence of CCl₃CH₂CH(CCL₃)CF₃, a product of recombination of the adduct radical and CCl₃, in the reaction mixture, which confirms the radical nature of the process. The structure of all the reaction products was confirmed by¹³C NMR and (or) mass spectrometry.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1807–1811, August, 1990.     

Multinuclear NMR spectra of (CH3)3SnCH2M(CH3)3 (MSn,Ge, Si,C) and some halogenated derivatives

Chemical shift and scalar coupling constant information has been obtained from the ¹H, ¹³C, ²⁹Si and ¹¹⁹Sn NMR spectra of a series of compounds (CH₃)₃SnCH₂M(CH₃)₃, where M = Sn, Ge, Si or C and with one or two CH₃? (Sn) groups replaced by Cl, Br or I. The (CH₃)₃M and (CH₃)₃MCH₂ groups appear to have opposite substituent effects on chemical shifts.     

Fluorophenylantimony carboxylates(II): synthetic and spectroscopic studies (UV, IR, H, F and C NMR) of pentafluorophenylantimony(V) di- and tetracarboxylates

Pentafluorophenylantimony(V) di- and tetracarboxylates of the molecular formula C₆F₅SbX₂L₂ (when X=L=OCOR (R=CH₃, CH₂Cl, CHCl₂, CCl₃, CF₃, CH₂OC₆H₃Cl₂-2,4, CH₂OC₆H₂Cl₃-2,4,5) and when X=Cl; L=OCOCH_3, OCOCHCl₂) have been synthesized by the metathetical reaction of pentafluorophenylantimony(V) tetrachloride and (dibromide)dichloride with corresponding sodium salt of carboxylic acids in appropriate molar ratio using 15-crown-5 as phase transfer catalyst. The van’t Hoff factor ‘i’ and molar conductance data of the compounds revealed them to be monomeric and non-conducting in nature. Elemental analysis, UV, IR and NMR (¹H, ¹⁹F and ¹³C) were used to characterize the derivatives. Compounds are tentatively assigned as a pentacoordinated square pyramidal structure in which carboxylate ligand behaving as a monodentate ligand.     

Phosphor–Kohlenstoff–Halogen-Verbindungen. XXV [1]. α-Trimethylsilyl-substituierte Methylphosphane: Darstellung und CCl4-Oxydation zu P-Chlor-methylenphosphoranen

Zwei Verfahren zur Darstellung α-trimethylsubstituierter Methylphosphane von genereller Anwendungsbreite werden vorgestellt. Phenylierte Vertreter PhPR? CH₂? Tms ( 2a— ) lassen sich durch Na-Spaltung in NH₃ und nachfolgende Kondensation mit Cl? CH₂? Tms gewinnen. Metallierung mit n-BuLi und TmsCl? Einwirkung führt zur Zweitsilylierung in αPosition ( 3a—d, f . Diorganylamino-funktionelle Derivate 5a—e und 6 sind vorteilhaft über eine Primäraktivierung (Grignardierung oder Lithiierung) der Silylmethan-Komponenten zu erhalten. Die oxidative Ylidierung mit CCl₄ ergibt nach Gl. (7) in allen Fällen P-Chlor-methylphosphorane. Außer durch Elementaranalyse wird die Konstitution sämtlicher Verbindungen durch die ³¹P{¹H}- und komplementären ¹³C{¹H}-Daten gesichert. Phosphorus-Carbon-Halogen Compounds. XXV. α-Trimethylsilyl-substituted Methylphosphanes: Synthesis and CCl₄? Oxidation to P-Chlor-methylene-phosphoranes Two procedures of general applicability for the synthesis of αxyltrimethylsilyl-substituted methylphosphanes are reported. Phenylated species PhPR? CH₂? Tms ( 2a—e ) can be obtained by Na cleavage in NH₃ and subsequent condensation with Cl? CH₂? Tms. Metallation with n-BuLi and treatment with TmsCl causes two-fold silylation in α-position ( 3a—d, f ). Diorganylamino-functionalized derivatives 5a—e and 6 are preferrably prepared by initial activation (grignardation or lithiation) of the silylmethane component. Oxidative ylidation with CCl₄ yields in all cases P-chloro-methylenephosphoranes according to eq. (7). The constitution of all compounds has been confirmed by ³¹P{¹H} and complementary ¹³C{¹H} data in addition to elemental analyses.     

Study on synthesis of lanthanide chelates of fluorochloroalkyl β-diketones useful as shift reagents

Several lanthanide chelates of the fluorochloroalkyl β-diketones Ln(CF₂ClCOCHCOR)₃ ·nH₂O were prepared (2, Ln=Eu; 2a, R=C(CH₃)₃, n=0; 2b, R=C₆F₅, n=0; 2c, R=CF₂Cl, n=2. 3, Ln=Pr; 3a, R=C (CH₃)₃, n=0; 3b, R=C₆F₅, n=l; 3c, R=CF₂Cl, n=2. 4, Ln=La, R=C₆H₅, n=0) and the NMR shift data of compounds 2 and 3 had been determined using alcohols, ether, ketones and amine as substrates. With alcohol, ether and ketone, compounds 2 induces shifts similar to that induced by Eu (fod)₃. However due to the high solubility of the chelates in non-polar organic solvents such as CHCl₃ and CCl₄ and the absence of ¹H signal from compounds 2b and 2c, their application as a series of new ¹H NMR shift reagents seems promising.     

A multinuclear NMR spectroscopy study of alkoxysilanes

¹⁷O, ²⁹Si, and ¹³C NMR spectra of more than 100 mono-, di-, tri- and tetra-alkoxysilanes R_4−nSi(OR′)_n; R = C_nH_2n+1, Ph, CH₂Cl, CH₂Br; R′ = C_nH_2n+1, CH₂Ph, CH₂CH₂Cl, CH₂CHCH₂, CH₂CCH, CH₂CF₃. (CH₂)₃Cl, (CH₂)₃CN have been studied.Linear relationships between the chemical shifts of ¹⁷O, ²⁹Si, ¹³C in alkoxysilanes and the inductive and steric constants of substituents R and R′ were observed. Different transmission of electronic effects along the SiO bond in various directions was revealed by means of ¹³C, ²⁹Si, ¹⁷O NMR spectroscopy and correlation analysis. The results are discussed in terms of (pd)_π-bonding between the oxygen and silicon atoms in compounds containing an SiO bond.     

Rate constants for reactions of Cl abstraction from CCl4 by CCl3CH2·CHR radicals and Br abstraction from CCl3CH2CHBrR (R=Bun, AcO, OCNC4H8, CN) by ·Re(CO)5 radicals

The rate constants for reactions of Cl abstraction from CCl₄ by CCl₃CH₂·CHR radicals and Br abstraction from CCl₃CH₂CHBrR (R=Buⁿ, AcO, OCNC₄H₈, CN) by·Re(CO)₅ radicals were determined by ESR spectroscopy using spin trapping technique. Replacement of H atoms at the C(β) atom by O or N atoms reduces the reactivity of the radicals in the reactions of Cl abstraction from CCl₄ by approximately an order of magnitude. The presence of two polar groups at the C(β) atom results in appreciable decrease in the strength of the C−Br bond in CCl₃CH₂CHBrR adducts. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 45–48, January, 2000.     

Empirical additive parameter and automatic assignment of 13C NMR signals of some aryl and heteroaryl groups. A new criterion for a linear relationship between 13C chemical shifts and charge densities

The ¹³C NMR signals of some mono- and disubstituted aryl compounds were assigned by means of empirical additive substituent parameters and information taken from fully coupled spectra. This assignment was compared with that obtained with the help of the method of automatic assignment of the signals based on the linear relationship between ¹³C chemical shift and charge density. The results show that in the cases of XR substituents (X = O, NH and R = H, CH₃, CH₂CH₂OH) a good correlation is observed and the automatic assignment is correct. In contrast, in the cases of ? CH₂CH₂Y substituents (Y = OH, NH₂, Cl) a worsening of the correlation is observed and the automatic assignment is not correct. It is suggested that for compounds with a preliminarily known assignment, the automatic assignment can serve as an additional criterion for the reliability of the linear relationship between ¹³C chemical shift and charge density.     

Bildung siliciumorganischer Verbindungen. XXXIX. Teilchlorierte Carbosilane

1. Photochlorination in CCl₄ of the Si-chlorinated carbosilanes (Cl₃Si? CH₂)₂SiCl₂ and (Cl₂Si? CH₂)₃ leads to totally chlorinated compounds, e. g. (Cl₃Si? CCl₂)₂SiCl₂. After chlorination has started at one CH₂ group, formation of a CCl₂ group is preferred before another CH₂ group is involved into the reaction. Thus preparation of compounds a, b, c is possible. Cl₃Si? CCl₂? SiCl₂? CH₂? SiCl₃ (a) for (b) and (c) (see “Inhaltsübersicht”). SO₂Cl₂ (benzoyl peroxide) as chlorinating agent reacts more slowly, and opens an access to carbosilanes containing CHCl groups such as (d), Cl₃Si-CHCl? SiCl₂? CH₂? SiCl₃ (e). Reactions of compounds (a) to (d) with LiAlH₄ yields carbosilanes with SiH groups, and partially chlorinated C atoms. 2. By the high reactivity of Si? CCl₂? Si groups an exchange of Cl atoms of CCl groups in perchlorinated carbosilanes is possible for H atoms of Si? H groups in perhydrogenated carbosilanes, thus allowing the preparation of compounds containing CHCl and SiHCl groups, e. g. according to Gl.(1) (Inhaltsübersicht). Further reactions, formulated as the last equations in Inhaltsübersicht, are reported as well as the rearrangement of H₃Si? CHCl? SiH₃.     

Deactivation of I(2P1/2) by CH3Cl,CH2Cl2, CHCl3, CCl3F,and CCl4

Collisional deactivation of I(²P_1/2) by the title compounds was investigated through the use of the time-resolved atomic absorption of excited iodine atoms at 206.2 nm. Rate constants for atomic spin-orbit relaxation by CH₃Cl, CH₂Cl₂, CHCl₃, CCl₃F, and CCl₄ are 3.1±0.3×10⁻¹³, 1.28±0.08×10⁻¹³, 5.7±0.3×10⁻¹⁴, 3.9±0.4×10⁻¹⁵, and 2.3±0.3×10⁻¹⁵cm³ molecule⁻¹ s⁻¹, respectively, at room temperature (298 K). The higher efficiency observed for relaxation by CH₃Cl, CH₂Cl₂, and CHCl₃ reveals a contribution in the deactivation process of the first overtone corresponding to the C(SINGLEBOND)H stretching of the deactivating molecule (which lies close to 7603 cm⁻¹) as well as the number of the contributing modes and certain molecular properties such as the dipole moment. It is believed that, for these molecules, a quasi-resonant (E-v,r,t) energy transfer mechanism operates. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet 30: 799–803, 1998     

Synthesis and Spectroscopic Study of Some New Phosphoramidates,Crystal Structures of N‐Benzoyl‐N′,N″‐bis(azetidinyl)phosphoric Triamide and N‐Benzoyl‐N′,N″‐bis(hexamethylenyl)phosphoric Triamide

Some new N‐carbonyl, phosphoramidates with formula C₆H₅C(O)N(H)P(O)R₂ (R = NC₃H₆ ( 1 ), NC₆H₁₂ ( 2 ), NHCH₂CH=CH₂ ( 3 ), N(C₃H₇)₂ ( 4 )) and CCl₃C(O)N(H)P(O)R′₂ (R′ = NC₃H₆ ( 5 ), NHCH₂CH=CH₂ ( 6 )) were synthesized and characterized by ¹H, ¹³C, ³¹P NMR and IR spectroscopy and elemental analysis. The structures were determined for compounds 1 and 2 . Compound 1 exists as two crystallographically independent molecules in crystal lattice. Both compounds 1 and 2 produced dimeric aggregates via intermolecular ‐P=O…H‐N‐ hydrogen bonds, which in compound 2 is a centrosymmetric dimer. In compounds with four‐membered ring amine groups, ³J(P,C)>²J(P,C), in agreement with our previous studies about five‐membered ring amine groups. Also, ³J(P,C) values in compounds 1 and 5 are greater than in compounds with five‐, six‐ and seven‐membered ring amine groups.     

1λ6,2,4-Thiadiazetidine und 1,2λ6,3-Oxathiazetidine

1λ⁶,2,4-Thiadiazetidines and 1,2λ⁶,3-Oxathiazetidines From the reaction of the sulfur triimides (RN?)₃S ( 2a R?(CH₃)₃C, 2b R?(CH₃)₃Si) with pentafluoroazapropene ( 11 ) the appropriate 1λ⁶,2,4 thiadiazetidines ( 13a, 13b ) are formed, while from ClSO₂N?CCl₂ ( 14 ) and 2a (CH₃)₃C? N?C?N? SO₂Cl ( 17 ) is isolated. 2b and hexafluoroacetone ( 18 ) give the rather unstable 1,2λ⁶,3-oxathiazetidine ( 20 ).     

Quantum-Chemical Study of the Electronic and Steric Structure of Vinyltetrazoles: II. 2-Vinyltetrazoles

The total Mulliken charges on the C and N atoms, populations of the S-trans-(N¹) conformers, and rotation barriers in the molecules of 2-vinyl-5-R-tetrazoles (R = H, CH₃, CH = CH₂, C₆H₅, CH₂Cl, CF₃) were calculated ab initio (HF/6-31G**, MP2/6-31G**). The results were compared with the ¹H and ¹³C NMR data for these compounds.