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Dichloroethylene, reaction

The terminal diyne 320 is prepared by coupling of the zinc acetylide 318 with /rfln.s-l-iodo-2-chloroethylenc (319), followed by elimination of HCI with sodium amide[231]. Similarly, terminal di- and triynes are prepared by using cw-l,2-dichloroethylene[232]. The 1-alkenyl or l-aryl-2-(perefluoroalkyl) acetylene 321 is prepared by the reaction of a zinc acetylide with halides[233]. [Pg.173]

Interestingly, 1,2-dichloroethylene can be used for coupling without activation of the chlorides. The reaction of c -1.2-dichloroethylene (331) has wide... [Pg.174]

Both chlorines of 1,1-dichloroethylene (340) react stepwise with different terminal alkynes to form the unsymmetrical enediyne 341 [250]. The coupling of the dichloroimine 342 with tin acetylide followed by hydrolysis affords the dialkynyl ketone 343[2511. The phenylthioimidoyl chloride 344 undergoes stepwise reactions with two different tin acetylides to give the dialkynylimine 345[252],... [Pg.176]

A trialkylsilyl group can be introduced into aryl or alkenyl groups using hexaalkyidisilanes. The Si—Si bond is cleaved with a Pd catalyst, and trans-metallation and reductive elimination afford the silylated products. In this way, 1,2-bis-silylethylene 761 is prepared from 1,2-dichloroethylene (760)[625,626], The facile reaction of (Me3Si)2 to give 762 proceeds at room temperature in the presence of fluoride anion[627]. Alkenyl- and arylsilanes are prepared by the reaction of (Me3Si)3Al (763)[628],... [Pg.241]

The rather unreactive chlorine of vinyl chloride can be displaced with nucleophiles by the catalytic action of PdCb. The conversion of vinyl chloride to vinyl acetate (797) has been studied extensively from an industrial standpoint[665 671]. DMF is a good solvent. 1,2-Diacetoxyethylene (798) is obtained from dichloroethylene[672]. The exchange reaction suffers steric hindrance. The alkenyl chloride 799 is displaced with an acetoxy group whereas 800 and 801 cannot be displaccd[673,674]. Similarly, exchange reactions of vinyl chloride with alcohols and amines have been carried out[668]. [Pg.246]

Dehydrochlorination of chlorinated derivatives such as 1,1,2-trichloroethane may be carried out with a variety of catalytic materials, including Lewis acids such as aluminum chloride. Refluxing 1,1,2-trichlorethane with aqueous calcium hydroxide or sodium hydroxide produces 1,1-dichloroethylene in good yields (22), although other bases such as magnesium hydroxide have been reported (23). Dehydrochlorination of the 1,1,1-trichloroethane isomer with catalytic amounts of a Lewis acid also yields 1,1-dichloroethylene. Other methods to dehydrochlorinate 1,1,1-trichloroethane include thermal dehydrochlorination (24) and by gas-phase reaction over an alumina catalyst or siUca catalyst (25). [Pg.509]

The trans isomer is more reactive than the cis isomer ia 1,2-addition reactions (5). The cis and trans isomers also undergo ben2yne, C H, cycloaddition (6). The isomers dimerize to tetrachlorobutene ia the presence of organic peroxides. Photolysis of each isomer produces a different excited state (7,8). Oxidation of 1,2-dichloroethylene ia the presence of a free-radical iaitiator or concentrated sulfuric acid produces the corresponding epoxide [60336-63-2] which then rearranges to form chloroacetyl chloride [79-04-9] (9). [Pg.20]

In the 1960s materials became available which are said to have been obtained by chlorination at lower temperatures. In one process the reaction is carried out photochemically in aqueous dispersion in the presence of a swelling agent such as chloroform. At low temperatures and in the presence of excess chlorine the halogen adds to the carbon atom that does not already have an attached chlorine. The product is therefore effectively identical with a hypothetical copolymer of vinyl chloride and symmetrical dichloroethylene. An increase in the amount of post-chlorination increases the melt viscosity and the transition temperature. Typical commercial materials have a chlorine content of about 66-67% (c.f. 56.8% for PVC) with a Tg of about 110% (c.f. approx. 80°C for PVC). [Pg.359]

During the investigation of the effect of the structure of the starting compound on its behavior in this reaction, it was found that N-methylated pyrazolyl ketones 12a-d can also be converted either into the normal products 13a-c, 14a-c via substitution of the carbonyl oxygen by chlorine or into the corresponding a,fi-dichloroethylenes 17a-d in 50-90% yields (76TZV2288) (Scheme 29). [Pg.15]

Thus, depending on the conditions, the reaction of methylpyrazolylketones with phosphorus pentachloride leads to products from substitution of the carbonyl oxygen by chlorine, o, /3-dichlorovinylpyrazoles, that can be dehydrohalo-genated with sodium amide to ethynylpyrazoles or to Q ,/3-dichloroethylenes. The... [Pg.16]

In a small sample of gas containing 12 molecules of cis-dichloroethylene, the reaction proceeds at an average rate of 1.5 molecules/s for 2.0 seconds, (a) Use line drawings to illustrate the small sample before the reaction begins, (b) Redraw the picture after 2.0 seconds of reaction. [Pg.1119]

O / O Miscellaneous Reactions. A study of the reactions of halogeno-olefins with phosphorus trichloride and oxygen has shown that phosphates [e.g. rra/i5-l,2-dichloroethylene gives 1,2,2-trichloroethyl phosphorodi-chloridate, (29)] are the major products. The minor product was identified as the analogous phosphonate (30), which had previously been reported... [Pg.45]

The reaction of /ra/w-l,2-dichloroethylene with phosphorus trichloride in the presence of oxygen has been shown to give the phosphorodichloridate (18), not the phosphonodichloridate (19) suggested previously. This reaction is almost certainly free-radical in character and possible chain mechanisms were proposed. [Pg.99]

The formation and reaction of peroxyl radicals derived by reaction of tervalent phosphorus compounds with oxygen have attracted interest. Photolysis of trialkyl phosphites in oxygenated solutions of aromatic hydrocarbons gives phenols. " Phosphorus trichloride reacts with 1,2-dichloroethylene, in the presence of oxygen, to give (17). It is tempting to suggest that both reactions occur via similar intermediates, e.g. (15) and (16). [Pg.232]

Many examples of photocycloaddition reactions of olefins and polyenes yielding cyclobutane derivatives have been reported. Irradiation of mixtures of butadiene and 1,1-dichloroethylene in the presence of a... [Pg.229]

The relative reactivity of cyclopentadiene and ds-dichloroethylene toward triplet cyclopentadiene was found to be greater than 20 1 while that for cyclopentadiene and trans-dichloroethylene is less than 5 1. Thus the trans isomer is about four times more reactive toward the triplet cyclopentadiene than the cis isomer. An interesting temperature dependence of the product distribution of this reaction has been reported (Table 10.8). The data in Table 10.8 indicate that the relative amount of 1,4 addition [products (39) and (40)] is much more sensitive to temperature than 1,2 addition [products (35)—(38)], especially for the trans-olefin. The data also indicate that some rotation about the CHC1-CHC1 bond occurs in intermediate radicals derived from both cis- and trans-dichloroethylene. However, rotational equilibrium is not established at ring closure since the ratios of ds-dichlorocyclobutanes... [Pg.231]

A good interaction diagram can be drawn, Fig. 10, for the reaction of cyclopentadiene with 1,1-dichloroethylene, Eq. 25. 87>... [Pg.173]

The regioselectivity of each one of the previously cited reactions, Eqs. 29—31, is well-correlated by the interaction diagram. The degenerate interaction of the bonding levels is controlling, and whether the reaction is concerted or biradical the major orientation should be as shown in 19. The olefin 1,1-dichloroethylene was taken as the model for 1,1-dimethoxy-ethylene. [Pg.176]

Sajus et al. [243,244] synthesized the peroxo complex of molybdenum(VI) and studied its reaction with a series of olefins. This peroxo complex M0O5 was proved to react with olefins with epoxide formation. The selectivity of the reaction increases with a decrease in the complex concentration. It was found to be as much as 95% at epoxidation of cyclohexene by M0O3 in a concentration 0.06 mol L-1 at 288 K in dichloroethylene [244], The rate of the reaction was found to be... [Pg.418]

The reaction proceeds as pseudomonomolecular reaction with a rate k at the constant olefin concetration. The values of k for epoxidation of olefins in dichloroethylene solutions at 288 K and an olefin concentration of 1.96 mol L 1 is given below [244]. [Pg.418]

Investigation of the concentration dependence of/13 of trichloroethylene and cis 1,2-dichloroethylene (Table 8) over the range of 50-100 mole % showed a small but significant change. Both cis and trans isomers of the dichloro and dibromoethylenes show the same slopes for the concentration dependence (Figs. 1 and 2). This is inconsistent with the idea of a reaction field effect since... [Pg.138]

The kinetics of chlorination of ethylene, allyl chloride, 3,4-dichlorobutene, 2,3-dichlo-ropropene, and 1,2-dichloroethylene in 1,2-dichloroethane have been investigated in the presence of BU4NCI. The mathematical treatment of the results was performed with due regard to the equilibrium constants of the formation of complexes between CI2 and CP. For all the substrates at 256K, the introduction of CP into the system has been found to result in an increase in the rate of the addition. The reaction turned out to be of first order with respect to both the substrate and the salt and second order with respect to chlorine. As expected, the dependence of the reaction rate on the substiments at the double bond is compatible with the electrophilic addition, initiated by electrophilic chlorine."... [Pg.421]

In batch kinetic tests, Yan and Schwartz (1999) investigated the oxidative treatment of chlorinated ethylenes in groundwater using potassium permanganate. 1,1-Dichloroethylene reacted more quickly than cis- and /ra/ 5-l, 2-dichloroethylene, trichloroethylene, and tetrachloroethylene. The reaction rate decreased with an increasing number of chlorine substituents. The pseudo-first-order rate constant and half-life for oxidative degradation (mineralization) of 1,1-dichloroethyene were 2.38 x 10 Vsec and 4.9 min, respectively. [Pg.419]

The following rate constants were reported for the reaction of rafl5-l,2-dichloroethylene and ozone in the atmosphere 1.8 x lO cmVmolecule-sec at 298 K (Atkinson and Carter, 1984) and... [Pg.421]

Source Hexachlorobenzene may enter the environment from incomplete combustion of chlorinated compounds including mirex, kepone, chlorobenzenes, pentachlorophenol, PVC, polychlorinated biphenyls, and chlorinated solvents (Ahling et al., 1978 Dellinger et al., 1991). In addition, hexachlorobenzene may enter the environment as a reaction by-product in the production of carbon tetrachloride, dichloroethylene, hexachlorobutadiene, trichloroethylene, tetrachloro-ethylene, pentachloronitrobenzene, and vinyl chloride monomer (quoted, Verschueren, 1983). [Pg.634]

Butler and Heyes (1998) investigated the reductive dechlorination of hexachloroethane in water by iron sulfide. Tetrachloroethylene was the major product with pentachloroethane as a minor intermediate. Final reaction products were trichloroethylene, c/s-1,2-dichloroethylene, and acetylene. The rate of reaction increased with increasing iron sulfide concentrations and pH. At pH 7.8, first-order rate constants were 0.0726, 0.086, and 0.533/h at iron sulfide concentrations of 10, 25, and 100 g/L, respectively. At an iron sulfide concentration of 100 g/L, first-order rate... [Pg.641]

Chemical/Physical. Products of hydrolysis include chloroacetaldehyde, 1,1-dichloroethylene, and HCl. The aldehyde is subject to hydrolysis forming hydroxyacetaldehyde and HCl (Kollig, 1993). The reported half-life for this reaction at 20 °C is 170 yr (Vogel et al., 1987). Under alkaline conditions, 1,1,2-trichloroethane hydrolyzed to 1,2-dichloroethylene. The reported hydrolysis half-life in water at 25 °C and pH 7 is 139.2 yr (Sata and Nakajima, 1979). [Pg.1091]

Yamada, T., El-Sinawi, A., Siraj, M., Taylor, P.H., Peng, J., Hu, X., and Marshall. P. Rate coefficients and mechanistic analysis for the reaction of hydroxyl radicals with 1,1-dichloroethylene and irans-l, 2-dichloroethylene over an extended temperature range, /. Phys. Chem. A, 105(32) 7588-7597, 2001. [Pg.1744]

In the presence of a [RuCl2(PPh3)3] catalyst N-methylmorphoHne-N-oxide (MMO) reacts with alcohols in dichloroethane or 1,2-dichloroethylene to afford mostly aldehydes together with carboxylic acids. Instead of the rather expensive MMO as reagent, a combination of N-methylmorphoHne and aqueous H2O2 (35 w%) could be used with similar results for the oxidation of long chain alcohols (1-octanol to 1-hexadecanol) [16]. At the end of the reaction the aqueous phase, containing the mthenium catalyst and methylmorphoHne could be recycled with no apparent loss of activity. [Pg.215]

The rates of radical-monomer reactions are also dependent on considerations of steric hindrance. This is easily observed by considering the reactivities of di, tri-, and tetrasubstituted ethylenes in copolymerization. Table 6-5 shows the kn values for the reactions of various chloroethylenes with vinyl acetate, styrene, and acrylonitrile radicals. The effect of a second substituent on monomer reactivity is approximately additive when both substituents are in the 1- or a-position. However, a second substituent when in the 2- or (3-position of the monomer results in a decrease in reactivity due to steric hindrance between it and the radical to which it is adding. Thus 2-10-fold increases and 2-20-fold decreases in the reactivities of vinylidene chloride and 1,2-dichloroethylene, respectively, are observed compared to vinyl chloride. [Pg.496]


See other pages where Dichloroethylene, reaction is mentioned: [Pg.175]    [Pg.12]    [Pg.345]    [Pg.347]    [Pg.14]    [Pg.1296]    [Pg.63]    [Pg.146]    [Pg.647]    [Pg.422]    [Pg.1086]    [Pg.1671]    [Pg.128]    [Pg.4]    [Pg.652]   
See also in sourсe #XX -- [ Pg.459 , Pg.460 , Pg.474 ]

See also in sourсe #XX -- [ Pg.459 , Pg.460 , Pg.474 ]

See also in sourсe #XX -- [ Pg.13 , Pg.155 ]




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1.1- Dichloroethylene

1.2- Dichloroethylenes

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