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1.
The synthesis of compounds involving a perfluorinated chain and a trichloromethyl group at the end of the chain is carried out by esterifying an alcohol with trichloracetic acid or by adding CCl4 to a perfluorinated alcohol acrylate. Cl3C? CO2? (CH2)2? C6F13 and Cl3C? CH2? CHCl? CO2? (CH2)2? C6F13 are obtained, respectively. These telogens are both used to initiate a polyacrylamide chain, thus allowing the synthesis of new highly hydrosoluble surfactants. The transfer constant of ferric chloride to the polyacrylamide chain can be calculated by studying the kinetics of the telomerization reaction. We found C = 16 at 125°C. Telomers can be prepared in which the polymer chain contains between 10 to 1000 acrylamide units; the degree of polymerization can be precisely predicted according to the amounts of products allowed to react.  相似文献   

2.
Radical acrylamide telomerization was carried out with three fluorinated telogens, C6F13C2H4I, C6F13I, and C6F13-C2H4SH with AIBN as initiator. Transfer constants were determined to be 40 × 10?4, 550 × 10?4, and 6500 × 10?4, respectively. Reactions were carried out in butyronitrile, a solvent which also transfers to the growing chain. In the telomerization, the intervention of the solvent, whose transfer constant was also determined, is evaluated quantitatively. Thus the formation of side products, which may reach proportions on the order of 50% compared with the telomer expected, can be explained.  相似文献   

3.
Unsaturated perfluoroalkyl esters derived from undecylenic acid: CH2?CH? (CH2)8? COO? CH2? CH2? RF (with RF?C6F13, 2a and RF?C8F17, 2b ) and C8F17? (CH2)10? COO? CH2? CH?CH2, 2c were prepared with excellent yields. Their hydrosilylation by methylhydrodimethylsiloxane copolymers of various Si? H contents gives new fluorinated polysiloxanes which were examined by 1H- and 13C-NMR, GPC, differential scanning calorimetry, and optical polarizing microscopy. Polymers derived from compounds 2a and 2b exhibit mesomorphic structures. © 1994 John Wiley & Sons, Inc.  相似文献   

4.
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.  相似文献   

5.
The synthesis of the nickel dialkynyl complex Ni(C?C? C6H4? C?CH)2(PPh3)2 and of the corresponding polyyne polymer containing nickel in the main chain ? [Ni(PPh3)2? C?C? C6H4? C?C? ]n are described and discussed. A new mixed solvent system DMSO/HNEt2 and homogeneous step-wise condensation method used for their synthesis are presented for the first time. The Ni-polyyne polymer obtained is dark yellow powder and soluble in THF or CH2Cl2. Its M?w is about 104, and the MWD is less than 2. Both the prepared complex and polymer have been characterized by IR, UV, 1H-NMR, and DTA. Preliminary results on photoluminesence of nickel polyyne polymers are present. © 1995 John Wiley & Sons, Inc.  相似文献   

6.
Formation of Organosilicon Compounds. 74. Synthesis and NMR-Spectra of Si-methylated and -chlorinated 2,2-Dichloro-1,3-disilapropanes and 2-Methyl-2-chloro-1,3-disilapropanes The compounds me3Si? CCl2? SimenCl3?n (n = 1–3; me = CH3) are synthesized by reaction of me3Si? CCl2Li (formed from me3Si? CCl2H with n-buLi, bu = butyl) with the appropriate methylchlorosilanes. The compounds Clme2Si? CCl2? SimenCl3?n are obtained by analogous reactions of (C6H5)me2Si? CCl2Li, cleavage of the Si-phenyl group with bromine and conversion of the Si? Br to the Si? Cl group with HCl in PCl3. The 2-methyl-2-chloro-1,3-disilapropanes are synthesized by lithination of the CCl2 group of 2,2-dichloro-1,3-disilapropanes, followed by reaction with meI. (Clme2Si)2CmeCl is obtained from (C6H5me2Si)2CCl2 by reaction with n-buLi to (C6H5me2Si)2 CClLi, which forms (C6H5me2Si)CClme with meI. Cleavage with bromine to (Brme2Si)2CClme and reaction with HCl/PCl3 leads to the expected compound. The influence of the substitution on the 1H, 13C and 29Si NMR spectra is investigated.  相似文献   

7.
The alkenyl substituted phenoxy–imine complexes [2‐C3H5‐6‐(2, 3, 5, 6‐C6F4H‐N?CH)C6H3O]2TiCl2 (C3H5=? CH2? CH?CH2 or ? CH?CH? CH3) are synthesized and characterized by 1H NMR, 13C NMR, and elemental analysis. When activated by MAO, they show high activity for the polymerization of ethylene to UHMWPE under different conditions (temperatures and polymerization time). Most of the resulting polymers have high molecular weights (>1.0 × 106 g·mol?1) and high melting points as well as crystallinity. To clarify the effect of the alkenyl group on the catalytic performance and the resultant polymer microstructure, the corresponding saturated complexes of type [2‐C3H7?6‐(2, 3, 5, 6‐C6F4H‐N?CH)C6H3O]2TiCl2 where C3H7 = –CH2? CH2? CH3 or ? CH(CH3)2 were synthesized and tested as catalysts in ethylene polymerization under the same reaction conditions. The microstructure and morphologies of these two species of PE samples were fully compared by the analysis of 13C NMR, GPC, DSC, and SEM. As a result, the allyl substituted complex show the highest activity to prepare the highest molecular weight polyethylene of all the catalysts. An interesting feature of the UHMWPE produced by these four catalysts is that they contain only a few short‐chain branches (mainly methyl, isobutyl and 2‐methylhexyl branches) in a low amount (<2.7 branches/1000 C). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3808–3818  相似文献   

8.
The end-functionalization of living polymers with bases (methanol, benzylamine, diethyl sodiomalonate, and sodium methoxide) and organosilicon compounds [X ? Si(CH3)3;X ? : CH2?C(CH3)COO? , CH3COO? , CH2?CHCH2? , C6H5? ] was investigated in the living cationic polymerization of styrene initiated with the 1-phenylethyl chloride/SnCl4/nBu4NCl system in CH2Cl2 at ?15°C. The four bases and C6H5SiMe3, independent of their structures, were apparently incapable of reacting with the living end and invariably led to polystyrenes with the ω-end chlorine [~ ~ ~ CH2CH(Ph)Cl] originated from the initiating system. The number-average end-functionality (F?n) of the chloride, determined by 1H-NMR, was close to unity (F?n > 0.9). The presence of chlorine in the polymer was also confirmed by elemental analysis. In contrast, the quenching by the trimethylsilyl compounds with X = methacryloxy, acetoxy, and allyl gave ω-end-functionalized polystyrenes with the corresponding terminal groups (X) for which the F?n values were close to unity (F?n > 0.9). The effects of the structure of silyl compounds on end-capping are also discussed. © 1994 John Wiley & Sons, Inc.  相似文献   

9.
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.  相似文献   

10.
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.  相似文献   

11.
The [C4H6O] ion of structure [CH2?CHCH?CHOH] (a) is generated by loss of C4H8 from ionized 6,6-dimethyl-2-cyclohexen-1-ol. The heat of formation ΔHf of [CH2?CHCH?CHOH] was estimated to be 736 kJ mol?1. The isomeric ion [CH2?C(OH)CH?CH2] (b) was shown to have ΔHf, ? 761 kJ mol?1, 54 kJ mol?1 less than that of its keto analogue [CH3COCH?CH2]. Ion [CH2?C(OH)CH?CH2] may be generated by loss of C2H4 from ionized hex-1-en-3-one or by loss of C4H8 from ionized 4,4-dimethyl-2-cyclohexen-1-ol. The [C4H6O] ion generated by loss of C2H4 from ionized 2-cyclohexen-1-ol was shown to consist of a mixture of the above enol ions by comparing the metastable ion and collisional activation mass spectra of [CH2?CHCH?CHOH] and [CH2?C(OH)CH?CH2] ions with that of the above daughter ion. It is further concluded that prior to their major fragmentations by loss of CH3˙ and CO, [CH2?CHCH?CHOH]+˙ and [CH2?C(OH)CH?CH2] do not rearrange to their keto counterparts. The metastable ion and collisional activation characteristics of the isomeric allenic [C4H6O] ion [CH2?C?CHCH2OH] are also reported.  相似文献   

12.
The first experimental evidence that fullerenes react with alkali‐metal trichloroacetates through a nucleophilic addition‐substitution route, yielding dichloromethylenefullerenes as the final products, is reported. The intermediates, C60(CCl3)? and C70(CCl3)? anions, have been isolated in their protonated forms as ortho‐C60(CCl3)H, as well as three ortho and one para isomer of C70(CCl3)H. The structures were unambiguously determined by means of 1H, 13C, and 1H–13C HMBC NMR spectroscopy along with UV/Vis spectroscopy. The observed regiochemistry was analyzed with the aid of quantum chemical calculations. Conversion of the protonated compounds into the [6,6]‐closed C60/70(CCl2) cycloadducts under basic conditions can be effected only for the ortho isomers, whereas para‐C70(CCl3)H decomposes back into pristine C70.  相似文献   

13.
A new efficient synthesis of functionalized perfluoroalkyl fluorophosphates by oxidative addition of Me2NCH2F to the electron‐deficient phosphanes (C2F5)nPF3?n (n=0–3) is reported. The initially formed zwitterionic, hexacoordinated phosphates [(C2F5)nF5?nP(CH2NMe2?CH2NMe2)] are converted into the corresponding phosphonium salts [(Me3PCH2NMe2]+[(C2F5)nF5?nP(CH2NMe2)]? by treatment with PMe3. In addition [(C2F5)3F2P(CH2NMe2?CH2NMe2)] can undergo a 1,3‐methyl shift from the internal to the terminal nitrogen—a structural characterization was achieved from the CF3 analogue. Reaction of [(C2F5)3F2P(CH2NMe?CH2NMe3)] and PMe3 gave rise to the formation of the zwitterionic phosphonium phosphate [(C2F5)3F2P(CH2NMe?CH2PMe3)], which was fully characterized by X‐ray diffraction analysis. Moreover, an efficient one‐pot synthesis of Cs+[(C2F5)3F2P(CH2NMe2)]? was pursued. This salt turned out to be a useful nucleophile in several alkylation reactions.  相似文献   

14.
Chemistry of Polyfunctional Molecules. 119 [1]. Tetracarbonyl-dicobalt-tetrahedrane Complexes with the Ligands Bis(diphenylphosphanyl)-amine, 2-Butin-1,4-diol, and tert.-Butylphosphaacetylene — Crystal Structure of the Phosphaalkyne Derivative Co2(μ-CO)2(CO)4(μ-Ph2P? NH? PPh2P,P′) · 1/2C6H5CH3 ( 4 · 1/2C6H5CH3) reacts with 2-butine-1,4-diol, HOCH2? C?C? CH2OH ( 5 ), to the dark-red tetrahedrane complex Co2(CO)4(μ-η22-HOCH2? C?C? CH2OH? C2, C3) · (μ-Ph2P? NH? PPh2? P,P′) · THF (6 · THF). With t-butyl-phosphaacetylene, tBu? C?P ( 7 ), 4 · THF forms Co2(CO)4(μ-η22-tBu? C?P)(μ-Ph2P? NH? PPh2? P,P′) ( 8 ), which also belongs to the tetrahydrane type. The compounds were characterized by their mass, IR, 31P{1H} NMR, 13C{1H} NMR, and1H NMR spectra. Crystals suitable for X-ray structure analyses have been obtained for 8 from dioxane. The dark red blocks crystallize in the monoclinic P21/c space group with the lattice constants a = 1404,1(5), b = 1330,0(7), c = 2578,8(10)pm; β = 90,82(3)°.  相似文献   

15.
In a theoretical investigation on Ziegler-Natta catalysis, the influence of the coordination number and ligand type of model compounds in relevant reaction steps were studied. Thus, by using the MEHT method, insertion reactions of ethylene into Zr–CH3 and Zr–H bonds were analyzed in systems of the type [Zr(C2H4)R4R′]?[Zr(Cp)(C2H4)R2R′], and [Zr(Cp)(C2H4)R3R′]?(R=R′=CH3, R=CH3, R′=H). It was found that all processes do not have significant kinetic barriers, whereas the reverse reactions in particular the β-hydride elimination have relatively high ones. The influence of coordination geometry and number on these transformations was found to be insignificant. While studying related conversions starting from [Zr(L)(C2H4)R3R′], [Zr(Cp)(C2H4)RR′(L)]+, and [Zr(Cp)(C2H4)R2R′(L)] (L = π-donor, R=R′=CH3 or R=CH3, R′=H) compounds a pronounced π-donor effect was observed. Methyl insertions in these cases showed a higher computed activation barrier than hydride migrations. An orbital basis for this phenomenon was provided and conclusions concerning chain-length control in Ziegler-Natta catalysis were drawn.  相似文献   

16.
By LiAlH4 (Cl3Si)2CH2, (Cl2Si? CH2)2SiCl2 are reduced to (H3Si)2CH2 (a), (H3Si? CH2)2SiH2 (b) and (H2Si? CH2)3(c). However with the compounds (Cl3Si)2CCl2, (Cl3Si? CCl202SiCl2 and (Cl2Si? CCl2)3 cleavages of the Si? C-bond and reduction of the CCl-groups occur apart from the normal reduction of the Si-Cl-groups to (H3Si)2CCl2 (d), (H3SiCCl2)2SiH2 (e) and (H2Si? CCl2)3. Excess LiAlH4 favours this cleavage, the exact amount of a quarter of a mole LiAlH4 per SiCl-group allows the formation of (d), (e), (f). The cleavage of (e) is in accordance with: (1), (2),(3). Therefore SiH34 and (H3Si)2CCl2 are the main-reaction-products and CH3SiH3 is formed acc. to equ. (3). Because of the cleavage of (H2Si? CCl2)3 with LiAlH4 H3Si? CCl2? SiH2? CH3and H3Si? CH2? SiH2? CH2? SiH2? CH3 are preferentially formed after the hydrolysis. The CH2-containing compounds (a), (b), (c) cannot be cleaved in an analogous reaction.  相似文献   

17.
Twelve new germanium substituted diphenyltin dipropionates with the general formula (R1GeCHR2‐CHR3COO)2SnPh2 where R1 = N(CH2CH2O)3, (C6H5)3 and (CH3C6H4)3, R2 = H, CH3, C6H5, p‐CH3C6H4, p‐CH3OC6H4, p‐ClC6H4, and R3 = H, CH3 have been synthesized by the reaction of diphenyltin oxide with a germanium substituted propionic acid. All the compounds were characterized by elemental analysis, IR, multi‐nuclear (1H, 13C, 119Sn) NMR and Mössbauer spectroscopies as well as mass spectrometry. The in vitro antibacterial activity of selected compounds is also reported.  相似文献   

18.
The reaction mechanisms for oxidation of CH3CCl2 and CCl3CH2 radicals, formed in the atmospheric degradation of CH3CCl3 have been elucidated. The primary oxidation products from these radicals are CH3CClO and CCl3CHO, respectively. Absolute rate constants for the reaction of hydroxyl radicals with CH3CCl3 have been measured in 1 atm of Argon at 359, 376, and 402 K using pulse radiolysis combined with UV kinetic spectroscopy giving ??(OH + CH3CCl3) = (5.4 ± 3) 10?12 exp(?3570 ± 890/RT) cm3 molecule?1 s?1. A value of this rate constant of 1.3 × 10?14 cm3 molecule?1 s?1 at 298 K was calculated using this Arrhenius expression. A relative rate technique was utilized to provide rate data for the OH + CH3 CCl3 reaction as well as the reaction of OH with the primary oxidation products. Values of the relative rate constants at 298 K are: ??(OH + CH3CCl3) = (1.09 ± 0.35) × 10?14, ??(OH + CH3CClO) = (0.91 ± 0.32) × 10?14, ??(OH + CCl3CHO) = (178 ± 31) × 10?14, ??(OH + CCl2O) < 0.1 × 10?14; all in units of cm3 molecule?1 s?1. The effect of chlorine substitution on the reactivity of organic compounds towards OH radicals is discussed.  相似文献   

19.
On Chalcogenolates. 151. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 1. Synthesis and Properties of N-Thioformyl Dithiocarbamates The N-thioformyl dithiocarbamates M[S2C? NH? CS? H], where M = K, Rb, Cs, Tl, NH4, [N(nC4H9)4], Na[S2C? NH? CS? H] · 0.5 H2O, and Ba[S2C? NH? CS? H]2 · 3 HO? CH2? CH2? OCH3 have been prepared by use of partial different procedures. The compounds were characterized with chemical and thermal methods as well as by means of electron absorption, infrared, nuclear magnetic resonance (1H and 13C), and mass spectra. Attempts to synthesize N-thioformyl dithiocarbamic acid were not successful.  相似文献   

20.
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.  相似文献   

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