Ethylene bromide, reaction with

Reaction.—a too c.c. flask to a short upright condenser (see Fig. 86) and to the upper end of the condensei attach a vertical delivery tube, dipping into an ammoniacal cuprous chloride solution. Pour 2—3 c.c. of ethylene bromide into the flask with 4 times its volume of strong methyl alcoholic potash, which is prepared by boiling methyl alcohol with excess of caustic potash on the water-bath with upright condenser. On gently heating, a rapid evolution of acetylene occurs and the characteristic brown copper compound (C2H,Cu,HjO) is precipitated from the cuprous chloride solution. 

Let s look at a typical polar process—the addition reaction of an alkene, such as ethylene, with hydrogen bromide. When ethylene is treated with HBr at room temperature, bromoethane is produced. Overall, the reaction can be formulated as... 

Bromoethylamine hydrobromide has been prepared by the reaction of potassium phthalimide with ethylene bromide, followed by hydrolysis,1 by the addition of hydrogen bromide to ethyleneimine,2 and by the present method.3... 

The nucleophilicity of the organocuprate cluster derives mainly from the filled copper 3d orbital, in combination with the carbon orbital associated with bonding to copper. These orbitals for the TS for reaction with methyl bromide and ethylene oxide are shown in Figure 8.4. 

The reaction between ethylene bromide and potassium iodide in 99% methanol (inert) has been found to be first-order with respect to each reactant (second-order overall) (Dillon, 1932). The reaction can be represented by C2liiBr2 + 3K1 —> C2H4 + 2KBr + KI3 or A + 3B - products. 

The atomic proportions of magnesium are not related to the mole quantity of hexachlorobenzene in this or any other entrainment reaction. The excess magnesium (1.1 g. atoms in this case) is used to react with ethylene bromide and leave 0.5 g. atom of dean-surfaced magnesium. Ordinarily 1 mole of entrainment reagent is used per mole of inert halide, but for this preparation 2 moles of entrainment reagent per mole of halide gives a better yield. 

Telechelic polymers, containing one or more end groups with the capacity to react with other molecules, are useful for synthesizing block and other copolymers [Fontanille, 1989 Hsieh and Quirk, 1996 Nuyken and Pask, 1989 Pantazis et al., 2003 Patil et al., 1998 Quirk et al., 1989, 1996 Rempp et al., 1988]. Living anionic polymers can be terminated with a variety of electrophilic reagents to yield telechelic polymers. For example, reaction with carbon dioxide, ethylene oxide, and allyl bromide yield polymers terminated with carboxyl, hydroxyl, and allyl groups, respectively. Functionalization with hydroxyl or carboxyl groups can also be achieved by reaction with a lactone or anhydride, respectively. Polymers with amine end... 

Tris[(2-perfluorohexyl)ethyl]tin hydride has three perfluorinated segments with ethylene spacers and it partitions primarily (> 98%) into the fluorous phase in a liquid-liquid extraction. This feature not only facilitates the purification of the product from the tin residue but also recovers toxic tin residue for further reuse. Stoichiometric reductive radical reactions with the fluorous tin hydride 3 have been previously reported and a catalytic procedure is also well established. The reduction of adamantyl bromide in BTF (benzotrifluoride) " using 1.2 equiv of the fluorous tin hydride and a catalytic amount of azobisisobutyronitrile (AIBN) was complete in 3 hr (Scheme 1). After the simple liquid-liquid extraction, adamantane was obtained in 90% yield in the organic layer and the fluorous tin bromide was separated from the fluorous phase. The recovered fluorous tin bromide was reduced and reused to give the same results. Phenylselenides, tertiary nitro compounds, and xanthates were also successfully reduced by the fluorous fin hydride. Standard radical additions and cyclizations can also be conducted as shown by the examples in Scheme 1. Hydrostannation reactions are also possible, and these are useful in the techniques of fluorous phase switching. Carbonylations are also possible. Rate constants for the reaction of the fluorous tin hydride with primary radicals and acyl radicals have been measured it is marginally more reactive than tributlytin hydrides. ... 

In a 3-1. round-bottomed flask fitted with a mechanical stirrer and a reflux condenser is placed 2.0 1. of anhydrous ethanol. To this is added 11.5 g. (0.5 g.-atom) of sodium cut into small pieces. When the sodium is completely dissolved, 23.6 g. (21.0 ml., 0.25 mole) of 1,2-ethanedithiol2 is added, followed by 47.0 g. (21.7 ml., 0.25 mole) of ethylene dibromide. The mixture is stirred and refluxed for 4 hours, cooled, and filtered to remove some sodium bromide mixed with polyethylene sulfide. The solid is washed with 100 ml. of ethanol, and the combined filtrates are distilled with stirring. When bumping becomes troublesome, as it generally does when 1.3-1.5 1. of distillate has been collected, the hot reaction mixture is filtered to remove sodium bromide, and the sodium bromide is washed with 100 ml. of hot ethanol. 

Ethylene chloride, 34, 85, 86 Ethylene chlorohydrm, 30, 11, 33, 11 Ethylene dibromide, 30, 35 reaction with disodium 1,2 ethanedithiol, 39, 23 Ethylene dnsothiuronium bromide,... 

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