From chloroethene

The name of a polymer is usually written with the prefix poly-(meaning many ) before the name of the monomer. Often the common name of the monomer is used, rather than the lUPAC name. For example, the common name of ethene is ethylene. Polyethene, the polymer that is made from ethene, is often called polyethylene. Similarly, the polymer that is made from chloroethene (common name vinyl chloride) is named polyvinylchloride (PVC). The polymer that is made from propene monomers (common name propylene) is commonly called polypropylene, instead of polypropene. 

APPLYING MODELS Polyvinyl chloride (PVC) is a polymer that is widely used in pipes and flooring. It is an addition polymer made from chloroethene, commonly known as vinyl chloride. 

Ethenyllithium (vinyllithium) is not generally prepared by direct deprotonation of ethene but rather from chloroethene (vinyl chloride) by metallation (Section 8-7). 

Alkenes are important industrial chemicals, particularly as raw materialsforthe manufacture of polymers. Ethene can be used to make poly(ethene). Ethene is used to make chloroethene, which is then used to make poly(chloroethene), and ethene is also used to make tetrafluoroethene, which is used to make poly(tetrafluoroethene). a Use displayed formulae to write an equation forthe formation of poly(chloroethene)from chloroethene. [3]... 

Solvent Evaporation from Solutions of Thermoplastic Polymers. A solution of a copolymer of vinyl chloride (chloroethene) [75-01-4] C2H2CI, vinyl acetate (acetic acid ethenyl ester) [108-05-4] and a hydroxy-functional vinyl monomer having a number average molecular... 

The plastic poly(chloroethene), PVC, is made from the monomer chloroethene, C2H3CI, by a polymerisation reaction. 

The only other alkenyl carbenoid with a proton trans to the halide that can readily be generated by deprotonation is the parent 1-lithio-l-chloroethene 57 [43] (Scheme 3.13). Insertion into organozirconocenes arising from hydrozirconation of alkenes and alkynes, followed by protonation, affords terminal alkenes and ( )-dienes 59, respectively [38]. The latter provides a useful complement to the synthesis of 54 in Scheme 3.12 since the stereocontrol is >99%. 

For instance, poly(vinyl chloride), derived from the polymerisation of vinyl chloride (chloroethene), CH2=CHC1, contains repeating units -CH2-CHCI-. However, long-chain molecules are of various lengths and the units are not necessarily all uniquely oriented and joined in a regular fashion, which would result in the polymer formulated -(CH2-CHC1)h. ... 

By contrast, vinyl halides such as chloroethene, CHj CHCl, and halogenobenzenes are very unreactive towards nucleophiles. This stems from the fact that the halogen atom is now bonded to an sp hybridised carbon, with the result that the electron pair of the C—Cl bond is drawn closer to carbon than in the bond to an sp hybridised carbon. The C—Q is found to be stronger, and thus less easily broken, than in, for example, CH3CH2CI, and the C—Q dipole is smaller there is thus less tendency to ionisation (8 1) and a less positive carbon for OH to attack Sf l) the n electrons of the double bond also inhibit the close approach of an attacking nucleophile. The double bond would not help to stabilise either the 8 y2 transition state or the carbocation involved in the 8 1 pathway. Very much the same considerations apply to halogenobenzenes, with their sp hybridised carbons and the tt orbital system of the benzene nucleus their reactions, which though often bimolecular are not in fact simply 8 2 in nature, are discussed further below (p. 170). 

Illustrative Example 5.1 Deriving Liquid Aqueous Solubilities, Aqueous Activity Coefficients, and Excess Free Energies in Aqueous Solution from Experimental Solubility Data Problem Calculate the Cf (L), yf 1 and G of (a) di-n-butyl phthalate, (b) y-1,2,3,4,5,6-hexachlorocyclohexane (y-HCH, lindane), and (c) chloroethene (vinyl chloride) at 25 °C using the data provided in Appendix C. 

The reactivity order also appears to correlate with the C-X bond energy, inasmuch as the tertiary alkyl halides both are more reactive and have weaker carbon-halogen bonds than either primary or secondary halides (see Table 4-6). In fact, elimination of HX from haloalkenes or haloarenes with relatively strong C-X bonds, such as chloroethene or chlorobenzene, is much less facile than for haloalkanes. Nonetheless, elimination does occur under the right conditions and constitutes one of the most useful general methods for the synthesis of alkynes. For example,... 

Apart from copper(I)-mediated reactions, few studies of the treatment of vinyliodonium salts with carbanions have appeared. The vinylations of the 2-phenyl- and 2- -hexyl-l,3-indandionate ions shown in equations 222 and 223 are the only reported examples of vinyliodonium-enolate reactions known to this author26,126. ( ,)-l-Dichloroiodo-2-chloroethene has been employed with aryl- and heteroarvllithium reagents for the synthesis of symmetrical diaryliodonium salts (equation 224)149,150. These transformations are thought to occur via the sequential displacement of both chloride ions with ArLi to give diaryl (/ -chlorovinyl)iodanes which then decompose with loss of acetylene (equation 225). That aryl(/ -chlorovinyl)iodonium chlorides are viable intermediates in such reactions has been shown by the conversion of ( )-(/ chlorovinyl)phenyliodonium chloride to diaryliodonium salts with 2-naphthyl- and 2-thienyllithium (equation 226)149,150. 

The novel cyclocarbaphosphanes, octahydro-l,2,3,4,5,6-hexamethyl[l,2,3]triphospholo[4,5-r/]-1,2,3-triphosphole (15) and its corresponding dehydro derivative (19) were synthesized by reaction of K2(PMe)4 THF with chloroethenes (Scheme 22). Thus cis- or trans-1,2-dichloroethene reacted with K2(PMe)4 2THF, formed in situ from potassium and pentamethylphosphide (101), to furnish a mixture of diastereoisomers (15) separation of which was achieved by repeated crystallizations < 78ZN(B)691,79ZC418). Analogous reaction with tetrachloroethene lead to the formation of compound (19) in 43% yield (Scheme 22). 

Even wider possibilities for the production of various nitroazoles are presented by l-nitro-2-halogenoethenes. Thus, the product from the cycloaddition of diazomethane to trans-l-nitro-2-chloroethene is 3-nitropyrazole (yield 65%) [485] (Scheme 66). 

When the above-mentioned process is applied to 1-lithio-l-chloroethene 66 [52] and vinyl zirconocene 67, arising from hydrozirconation of terminal alkynes, a stereospecific formation of 2-zirconated dienes 68 is obtained, affording terminal dienes after protonation [53] (Scheme 24). 

Three examples of the many reactions that can be advantageously carried out in high-temperature molten salts have been selected to illustrate this molten-salt technique. When 1,1-dichloroethane is passed through a ZnCl2/KCl melt at 330 °C, chloroethene is formed in 97 cmol/mol yield by dehydrohalogenation. Likewise, the addition of hydrogen chloride to acetylene proceeds with 89 cmol/mol yield in the same melt. A combination of these two steps allows a ready synthesis of the technically important chloroethene from acetylene and 1,1-dichloroethane according to Eq. (3-1) [25, 31]. 

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