Chlorine reaction with alkenes

Antimony(V) chloride (SbQj) and molybdenum(V) chloride (MoCls) can react spontaneously with alkenes to give predominantly the corresponding c/s-1,2-dichlorides (equation 11). The reaction probably proceeds through a successive insertion and reductive elimination sequence. The chlorination of butadiene with SbCls and copper(II) chloride results preferentially in the formation of (Z)- and ( )-1,4-dichloro adducts, while the reaction with chlorine gives an 1 1 mixture of 1,2- and 1,4-adducts, as shown in Table 2 and equation (12). The formation of (Z)-l,4-dichloro-2-butene may be ascribed to a transition state as shown in Scheme 3. 

Cyclic compounds undergo the same reactions as noncyclic compounds. For example, cyclic alkanes and cyclic alkenes undergo radical substitution reactions with chlorine or bromine (Scheme 4.24). 

Alkynes show the same kind of addition reactions with chlorine and bromine that alkenes do. 

Compounds with multiple bonds are capable of reacting with other molecules so as to acquire only cr bonds. A few such ADDITION reactions are illustrated for alkenes, alkynes, and carbonyl compounds. Ethylene, a typical alkene, reacts with chlorine readily at room temperature ... 

Reaction of HOCl, formed from calcium hypochlorite and CO2, with highly substituted alkenes in CH2CI2 is a convenient route to aHyUc chlorides (111). Ketones are chlorinated to a-chloroketones by reaction with HOCl Acetone initially gives CH2COCH2CI (112). Methyl ethyl ketone gives 78% CH3CHCICOCH3, 15% CH3CH2COCH2CI, and 7% dichlorides (113). 

A chlorohydrin has been defined (1) as a compound containing both chloio and hydroxyl radicals, and chlorohydrins have been described as compounds having the chloro and the hydroxyl groups on adjacent carbon atoms (2). Common usage of the term appHes to aUphatic compounds and does not include aromatic compounds. Chlorohydrins are most easily prepared by the reaction of an alkene with chlorine and water, though other methods of preparation ate possible. The principal use of chlorohydrins has been as intermediates in the production of various oxitane compounds through dehydrochlorination. 

Chirality center, 292 detection of, 292-293 Eischer projections and, 975-978 R,S configuration of, 297-300 Chitin, structure of, 1002 Chloral hydrate, structure of, 707 Chloramphenicol, structure of, 304 Chlorine, reaction with alkanes, 91-92,335-338 reaction with alkenes, 215-218 reaction with alkynes, 262-263 reaction with aromatic compounds, 550 Chloro group, directing effect of, 567-568... 

The chemistry of silicone halides was recently reviewed by Collins.13 The primary use for SiCU is in the manufacturing of fumed silica, but it is also used in the manufacture of polycrystalline silicon for the semiconductor industry. It is also commonly used in the synthesis of silicate esters. T richlorosilane (another important product of the reaction of silicon or silicon alloys with chlorine) is primarily used in the manufacture of semiconductor-grade silicon, and in the synthesis of organotrichlorosilane by the hydrosilylation reactions. The silicon halohydrides are particularly useful intermediate chemicals because of their ability to add to alkenes, allowing the production of a broad range of alkyl- and functional alkyltrihalosilanes. These alkylsilanes have important commercial value as monomers, and are also used in the production of silicon fluids and resins. On the other hand, trichlorosilane is a basic precursor to the synthesis of functional silsesquioxanes and other highly branched siloxane structures. 

A further support for the identification of the species responsible for the unimolecular conductance increase in terms of a chlorine-containing radical is the fact that in a blank experiment, i.e. one in which chloride is left out, a slow conductance increase is not observed and the overaU conductance yield is only half of that in the presence of chloride. Since in isobutene-saturated aqueous solution the lifetime of SOi is only 90 ns due to its rapid reaction with the alkene (as determined by optical experiments at 450 nm) [46], the non-observability of a unimolecular conductance increase means that the rate constant for heterolysis of the SO adduct to isobutene is 10 s" (cf. Eq. 32) ... 

Alkenes react with dinitrogen pentoxide in chlorinated solvents to give a mixture of /3-nitro-nitrate, vic-dinitro, vic-dinitrate ester and nitroalkene compounds. At temperatures between -30 °C and -10 °C the /3-nitro-nitrate is often the main product. The /3-nitro-nitrates are inherently unstable and readily form the corresponding nitroalkenes." Propylene reacts with dinitrogen pentoxide in methylene chloride between -10 °C and 0°C to form a mixture of l-nitro-2-propanol nitrate (27 %) and isomeric nitropropenes (12 %). The same reaction with cyclohexene is more complicated." ... 

Table 6.14 gives the rate constants for the reactions of chlorine atoms with some simple alkenes and some biogenic hydrocarbons. As expected, the reactions are... 

TABLE 6.14 Some Reported Values of the Rate Constants for the Reactions of Chlorine Atoms with Some Alkenes at 1 atm Total Pressure and 298 K... 

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