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1.
It is shown that the KINNEAR -PERREN reaction with ClCH2CH2Cl, PCl3, and AlCl3 produces the two possible isomers ClCH2CH2P(O)Cl2 and CH3CHClP(O)Cl2. Methods for the preparation of pure ClCH2CH2P(O)Cl2 and pure CH3CHClP(O)Cl2 are described. The physical properties of a number of chloroethyl groups containing phosphorus compounds are listed.  相似文献   

2.
Insertion of hexafluoropropene under thermal and/ or photochemical conditions occurs into C-H bonds of the halogenomethanes MeCl, CH2Cl2, CHCl3, MeF, CH2F2 and CHF2Cl and the fluoroethanes EtF, MeCHF2 and MeCF3, into CH and CCl bonds of the monochloroalkanes EtCl, MeCHFCl, prnCl, priCl, ButCl and BuiCl and into CCl bonds of allyl chloride and the chloroalkanes CH2ClCH2Cl, MeCHCl2, CH2ClCHCl2 and MeCCl3.  相似文献   

3.
The Cl atom-initiated oxidation of CH2Cl2 and CH3Cl was studied using the FTIR method in the photolysis of mixtures typically containing Cl2 and the chlorinated methanes at 1 torr each in 700 torr air. The results obtained from product analysis were in general agreement with those reported by Sanhueza and Heicklen. The relative rate constant for the Cl atom reactions of CH2Cl2 and CH3Cl was determined to be k(Cl +CH3Cl)/k(Cl + CH2Cl2) = 1.31 ± 0.14 (2σ) at 298 ± 2 K.  相似文献   

4.
The recombination of CF2Cl with CH2Cl and CFCl2 with CH2F were employed to generate CF2ClCH2Cl* and CFCl2CH2F* molecules with 381 and 368 kJ mol?1, respectively, of vibrational energy in a room‐temperature bath gas. The unimolecular reactions of these molecules, which include HCl elimination, HF elimination, and isomerisation by interchange of chlorine and fluorine atoms, were characterized. The three rate constants for CFCl2CH2F were 2.9×107, 0.87×107 and 0.04×107 s?1 for HCl elimination, isomerisation and HF elimination, respectively. The isomerisation reaction must be included to have a complete characterization of the unimolecular kinetics of CFCl2CH2F. The rate constants for HCl elimination and HF elimination from CF2ClCH2Cl were 14×107and 0.37×107 s?1, respectively. Isomerisation that has a rate constant less than 0.08×107 s?1 is not important. These experimental rate constants were matched to calculated statistical rate constants to assign threshold energies, which are 264, 268, and 297 kJ mol?1, respectively, for isomerisation, HCl elimination, and HF elimination for CFCl2CH2F and 314, 251, and 289 kJ mol?1 in the same order for CF2ClCH2Cl. Density functional theory was used to evaluate the models that were needed for the statistical rate constants; the computational method was B3PW91/6‐31G(d′,p′). Threshold energies for the unimolecular reactions of CF2ClCH2Cl and CFCl2CH2F are compared to those for CF2ClCH3 and CFCl2CH3 to illustrate the elevation of threshold energies by F‐ or Cl‐atom substitution at the beta carbon atom (identified by CH). The DFT calculations systematically underestimate the threshold energy for HCl elimination.  相似文献   

5.
The rate coefficients for the reactions of Cl atoms with CH3Br, (k1) and CH2Br2, (k2) were measured as functions of temperature by generating Cl atoms via 308 nm laser photolysis of Cl2 and measuring their temporal profiles via resonance fluorescence detection. The measured rate coefficients were: k1 = (1.55 ± 0.18) × 10?11 exp{(?1070 ± 50)/T} and k2 = (6.37 ± 0.55) × 10?12 exp{(?810 ± 50)/T} cm3 molecule?1 s?1. The possible interference of the reaction of CH2Br product with Cl2 in the measurement of k1 was assessed from the temporal profiles of Cl at high concentrations of Cl2 at 298 K. The rate coefficient at 298 K for the CH2Br + Cl2 reaction was derived to be (5.36 ± 0.56) × 10?13 cm3 molecule?1 s?1. Based on the values of k1 and k2, it is deduced that global atmospheric lifetimes for CH3Br and CH2Br2 are unlikely to be affected by loss via reaction with Cl atoms. In the marine boundary layer, the loss via reaction (1) may be significant if the Cl concentrations are high. If found to be true, the contribution from oceans to the overall CH3Br budget may be less than what is currently assumed. © 1994 John Wiley & Sons, Inc.  相似文献   

6.
A solution of AlCl3 in CH2Cl2 prepared in advance was used 18 days after the mixing of the components as an initiation system in the polymerization of isobutylene performed in CH2Cl2 in the temperature range between ?10 and ?20°C. The 1H-NMR analysis of polyisobutylene (PIB) samples synthesized to low and high conversion showed that it is the initiation reaction and not the transfer reaction to dichloromethane that is responsible for the ? CH2Cl endgroup in the polymer chain. In case of the transfer to monomer formation of PIB with internal terminal unsaturation [PIB? CH?C(CH3)2] is preferred to external unsaturation [PIB? CH2(CH3)C?CH2]. The solutions of AlCl3 in CH2Cl2 showed an absorption band at λmax = 302 nm.  相似文献   

7.

The interaction of Bu2Sn(OPri)2 with a trifunctional tetradentate Schiff base (LH3) (where H3L = HOC6H4CH═NCH3C(CH2OH)2) yields the precursor complex Bu2Sn(LH) 1, which, on equimolar reactions with different metal alkoxides [Al(OPri)3, Bu3Sn(OPri), Ge(OEt)4]; Al(Medea)(OPri) (where Medea = CH3N- (CH2CH2O)2); and Me3SiCl in the presence of Et3N], affords, respectively, the complexes Bu2Sn(L)Al(OPri)2 2, Bu2Sn(L)Al(Medea) 3, Bu2Sn(L)Bu3Sn 4, Bu2Sn(L)Ge(OEt)3 5, and Bu2Sn(L)SiMe3 6. The reactions of 2 with 2,5-dimethyl-2,5-hexanediol in a 1:1 ratio and with acetylacetone (acacH) in a 1:2 molar ratio afforded derivatives Bu2Sn(L)Al(OC(CH3)2CH2CH2C(CH3)2 O) 7 and Bu2Sn(L)Al(acac)2 8, respectively. All of the derivatives 18 have been characterized by elemental analyses, molecular weight measurements, and spectroscopic [IR and NMR (1H, 119Sn, 29Si, and 27Al)] studies.  相似文献   

8.
Formation and Reactions of the CH2Li‐Derivatives of tBu2P–P=P(CH3)tBu2 and (Me3Si)tBuP–P=P(CH3)tBu2 With nBuLi, (Me3Si)tBuP–P=P(CH3)tBu2 ( 1 ) and tBu2P–P=P(CH3)tBu2 ( 2 ) yield (Me3Si)tBuP–P=P(CH2Li)tBu2 ( 3 ) and tBu2P–P=P(CH2Li)tBu2 ( 4 ), wich react with Me3SiCl to give (Me3Si)tBuP–P=P(CH2–SiMe3)tBu2 ( 5 ) and tBu2P–P=P(CH2–SiMe3)tBu2 ( 6 ), respectively. With tBu2P–P(SiMe3)–PtBuCl ( 7 ), compound 3 forms 5 as well as the cyclic products [H2C–P(tBu)2=P–P(tBu)–PtBu] ( 8 ) and [H2C–P(tBu)2=P–P(PtBu2)–P(tBu)] ( 9 ). Also 3 forms 8 with tBuPCl2. The cleavage of the Me3Si–P‐bond in 1 by means of C2Cl6 or N‐bromo‐succinimide yields (Cl)tBuP–P=P(CH3)tBu2 ( 10 ) or (Br)tBuP–P=P(CH3)tBu2 ( 11 ), resp. With LiP(SiMe3)2, 10 forms (Me3Si)2P–P(tBu)–P=P(CH3)tBu2 ( 12 ), and Et2P–P(tBu)–P=P(CH3)tBu2 ( 13 ) with LiPEt2. All compounds are characterized by 31P NMR Data and mass spectra; the ylide 5 and the THF adduct of 4 additionally by X‐ray structure analyses.  相似文献   

9.
An analysis of thermochemical and kinetic data on the bromination of the halomethanes CH4–nXn (X = F, Cl, Br; n = 1–3), the two chlorofluoromethanes, CH2FCl and CHFCl2, and CH4, shows that the recently reported heats of formation of the radicals CH2Cl, CHCl2, CHBr2, and CFCl2, and the C? H bond dissociation energies in the matching halomethanes are not compatible with the activation energies for the corresponding reverse reactions. From the observed trends in CH4 and the other halomethanes, the following revised ΔH°f,298 (R) values have been derived: ΔH°f(CH2Cl) = 29.1 ± 1.0, ΔH°f(CHCl2) = 23.5 ± 1.2, ΔHf(CH2Br) = 40.4 ± 1.0, ΔH°f(CHBr2) = 45.0 ± 2.2, and ΔH°f(CFCl2) = ?21.3 ± 2.4 kcal mol?1. The previously unavailable radical heat of formation, ΔH°f(CHFCl) = ?14.5 ± 2.4 kcal mol?1 has also been deduced. These values are used with the heats of formation of the parent compounds from the literature to evaluate C? H and C? X bond dissociation energies in CH3Cl, CH2Cl2, CH3Br, CH2Br2, CH2FCl, and CHFCl2.  相似文献   

10.
Secondary Phosphine Chalcogenides. VII. Synthesis of Bis(tert.-butylphosphino)thane, ButHPCH2CH2PHBut, and 1-tert.-Butylphosphino-2-diphenylphosphinoethane, Ph2PCH2CH2PHBut, as well as their Secondary Phosphine Chalcogenides The reaction of Cl2PCH2CH2PCl2 with ButMgCl gives ButClPCH2CH2PClBut which is either hydrolysed to yield ButH(O)PCH2CH2P(O)HBut or reduced to give ButHPCH2CH2PHBut. This phosphine reacts with sulfur or selenium to give ButH(E)PCH2CH2P(E)HBut (E = S, Se). Treatment of Ph2PCH2CH2Cl with LiPHBut results Ph2PCH2CH2PHBut which is oxidized to give Ph2(E)PCH2CH2P(E)HBut (E = O, S, Se). The Ph2P group appears to be oxidized primarily. The compounds obtained are characterized by means of I.R. 1H and 31P-N.M.R. spectroscopy.  相似文献   

11.
Chloroselenates with Di- and Tetravalent Selenium: 77Se-NMR-Spectra, Syntheses, and Crystal Structures of (PPh4)2SeCl6 · 2 CH2Cl2, (NMe3Ph)2SeCl6, (K-18-crown-6)2SeCl6 · 2 CH3CN, PPh4Se2Cl9, (NEt4)2Se2Cl10, (PPh4)2Se3Cl8 · CH2Cl2, and (PPh4)2Se4Cl12 · CH2Cl2 The title compounds were obtained from reactions of selenium and selenium tetrachloride with PPh4Cl, NEt4Cl, NMe3PhCl, or (K-18-crown-6)Cl in dichloromethane or acetonitrile. (PPh4)2Se3Cl8 · CH2Cl2 was also formed from GeSe, PPh4Cl and chlorine in acetonitrile. The 77Se-NMR spectra of the solutions show the presence of dynamical equilibria which, depending on composition, mainly contain SeCl2, SeCl4, Se2Cl2, SeCl62–, Se2Cl62–, and/or Se2Cl102–. Solutions of AsCl3 and (PPh4)2Se4 in acetonitrile upon chlorination with Cl2 or PPh4AsCl6 yielded (PPh4)2Se2Cl6, while (PPh4)2As2Se4Cl12 was the product after chlorination with SOCl2. According to the X-ray crystal structure analyses the ions SeCl62–, Se2Cl9, and Se2Cl102– have the known structures with octahedral coordination of the Se atoms. The structure of the Se3Cl82– ion corresponds to that of Se3Br82– consisting of three SeCl2 molecules associated via two Cl ions. (PPh4)2Se4Cl12 · CH2Cl2 is isotypic with the corresponding bromoselenate and contains anions in which three SeCl2 molecules are attached to a SeCl62– ion; there is a peculiar Se–Se interaction.  相似文献   

12.
The Phosphinophosphinidene-phosphoranes tBu2P? P = P(R)tBu2 from Li(THF)22-(tBu2P)2P] and Alkyl Halides We report the formation of tBu2P? P = P(R)tBu2 a and (tBu2)2PR b (with R = Me, Et, nPr, iPr, nBu, PhCH2, H2C = CH? CH2 and CF3) reactions of Li(THF)22-(tBu2P)2P] 2 with MeCl, MeI, EtCl, EtBr, nPrCl, nPrBr, iPrCl, nBuBr, PhCH2Cl, H2C = CH? CH2Cl or CF3Br. In THF solutions the ylidic compounds a predominate, whereas in pentane the corresponding triphosphanes b are preferrably formed. With ClCH2? CH = CH2 only b is produced; CF3Br however yields both tBu2P? P = P(Br)tBu2 and tBu2P? P = P(CF3)tBu2, but no b . The ratio of a:b is influenced by the reaction temperature, too. The compounds tBu2P? P = P(Et)tBu2 4a and (tBu2P)2PEt 4 b , e. g., are produced in a ratio of 4:3 at ?70°C in THF, and 1:1 at 20°C; whereas 1:1 is obtained at ?70°C in pentane, and 1:2 at 20°C. Neither tBuCl nor H2C = CHCl react with 2 . The compounds a decompose thermally or under UV irradiation forming tBu2PR and the cyclophosphanes (tBu2P)nPn.  相似文献   

13.
Collisional deactivation of I(2P1/2) 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  相似文献   

14.
4-Methyl-1,2,3,5-dithiadiazolium Salts. Crystal Structures of(CH3CN2S2)5[CoCl4]Cl3 and (CH3CN2S2)Cl 4-Methyl-1,2,3,5-dithiadiazolium tetrachlorocobaltate trichloride, (CH3CN2S2)5[CoCl4]Cl3, was obtained by reaction of trithiazyl chloride, (NSCl)3, with CoCl2 in acetonitrile; it forms brown, moisture sensitive crystals. With tetraphenylarsonium chloride in CH2Cl2 it yields yellow crystalline (CH3CN2S2)Cl and (AsPh4)2CoCl4. The IR spectra of the title compounds are reported and assigned. Theit crystal structures were determined by X-ray diffraction. Crystal data: (CH3CN2S2)5[CoCl4]Cl3, orthorhombic, P212121, Z = 4, a = 830, b = 1603, c = 2443 pm at 180 K (structure determination with 1787 observed independent reflexions, R = 0.070); (CH3CN2S2)Cl, triclinic, P212121, Z = 4, a = 749, b = 819, c = 1015 pm, α = 84.9, β = 67.4, γ = 84.6° at 296 K (2653 reflexions, R = 0.040). Both compounds are ionic, having chloride and distorted tetrahedral CoCl42? anions and planar 4-methyl-1,2,3,5-dithiadiazolium cations which nearly fulfill C2v symmetry. The (CH3CN2S2)5[CoCl4]Cl3 structure contains five symmetry independent cations, (CH3CN2Cl has two symmetry independent cations, all being nearly equal. No nitrogen atom but all sulfur atoms of the cations have contact with three to five chlorine atoms, and as a rule there is one chloride ion which is coplanar with the cation and exhibits rather short distances to both S atoms (288 to 309 pm); therefore, the positive charge of the cations must be concentrated on the sulfur atoms.  相似文献   

15.
The 13C shielding of the isotopomers CH3Cl, CH2 DCl, CHD2Cl, and CD3Cl has been calculated for a range of temperatures from an self-consistent field (SCF) shielding surface computed by Buckingham and Olegario. It is found that each successive deuterium substitution increases the shielding by about 0.19 ppm and that a very slight nonadditivity occurs. The principal factor which governs the nuclear motion correction for each isotopomer is the stretching of the bonds with both first- and second-order terms being significant. Angle bending contributions are very small at first order but quite substantial at second order. Not only should the 13C-isotope shifts in this experimentally uninvestigated series be easily measured but the temperature dependence of the shielding in any one isotopomer should be observable provided that careful measurements are made. The 13C-shielding difference between CH3 35Cl and CH3 37Cl has also been calculated and is found to agree well with experiment. © 1996 John Wiley & Sons, Inc.  相似文献   

16.
Five-coordinated Complexes of Osmium (VIII) and Rhenium (VII). Crystal Structure of PPh4[OsO4Cl] · CH2Cl2 The five-coordinated anionic complexes [OsO4Cl]?, [OsO4N3]?, and [ReO3Cl2]? were isolated as tetraphenylphosphonium salts from reactions of OsO4 and ReO3Cl with PPh4Cl and PPh4N3, respectively, in dichloromethane solution. The compounds which are characterized by their i.r. spectra, are thermally sensitive and form crystalline powders with colours ranging from orange to violet. The crystal structure of PPh4[OsO4Cl] · CH2Cl2 was determined and refined with X-ray diffraction data. (4212 independent, observed reflexions, R = 0.032). It crystallizes in the monoclinic space group P2/b with four formula units per unit cell. The cell dimensions are at ?110°C a = 1754, b = 2184 pm, c = 692 and γ = 106.7°. The structure consists of tetraphenylphosphonium cations and anions [OsO4Cl]? with five-coordinated Os atoms in a trigonal bipyramidal geometry with the chlorine ligand in an axial position. The anion can also be regarded as a OsO4 tetrahedron, monocapped by a chloride ion. Each chloride ion is linked with two CH2Cl2 molecules via hydrogen bridges, forming chains in the direction c. The Os? Cl bond length (276 pm) is very long; the average OsO distance (172 pm) corresponds to that in the OsO4 molecule (170 pm).  相似文献   

17.
(PPh4)2[V2Cl9][VCl5] · CH2Cl2. Synthesis, I.R. Spectrum, and Crystal Structure The title compound was obtained by addition of CCl4 to a solution of PPh4Cl and excess VCl4 in CH2Cl2. It forms black crystals which are light and moisture sensitive. The i.r. spectrum is reported. The crystal structure was determined by X-ray diffraction (3044 independent reflexions, R = 0.063). Crystal data: triclinic, space group P1 , Z = 2, a = 1186, b 1325, c = 1995 pm, α 97.5, β 105.6°, γ 93.4°. The structure consists of PPh4+ cations, V2Cl9? and VCl5? anions and CH2Cl2 molecules. The V2Cl9? ions consist of face-sharing octahedra with a long V…?V distance of 333 pm; the VCl5? ions form nearly ideal trigonal bipyramids with V? Cl bonds of 228 pm (axial) and 218 pm (equatorial). Both anions deviate only marginally from D3h symmetry. Half of the cations is arranged to (PPh4+)2 pairs about inversion centers.  相似文献   

18.
The crystal structures have been determined of CH3NH3HgCl3, (CH3NH3)2HgCl4, and CH3NH3Hg2Cl5. In (CH3NH3)2HgCl4 the HgII atom is tetrahedrally coordinated by four Cl atoms with Hg? Cl bond lengths of 2.464 to 2.478 Å. In the other two compounds the HgII atom is involved in two short covalent Hg? Cl bonds, forming a pseudo HgCl2 molecule and two much longer bridging Hg? Cl bonds. The methylammonium groups are connected by hydrogen bonds to the chlorine atoms. The nature of the hydrogen bonding scheme probably causes disorder of the methylammonium groups.  相似文献   

19.
For the reactions of RP(O)(NHBut)Cl mth PriNH2 and ButNH2 in CH2Cl2, relative rates and product ratios suggest an elimination-addition mechanism uith a reactive (monomeric) metaphosphonimidate intermediate.  相似文献   

20.
The abstraction of the halogenide ligands in [Re(CH3CN)2Cl4]? should result in a solvent‐only stabilized ReIII complex. The reactions of salts of [Re(CH3CN)2Cl4]? with silver(I) and thallium(I) salts were investigated and the solid‐state structures of cis‐[Re(CH3CN)2Cl4]·CH3CN and cis‐[Re(NHC(OCH3)CH3)2Cl4] are described.  相似文献   

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