t'ədī`ēn), colorless, gaseous hydrocarbon. There are two structural isomers of butadiene; they differ in the location of the two carbon-carbon double bonds in the butadiene molecule. One (1,2-butadiene) has the formula CH2:C:CHCH3. The other (1,3-butadiene), often called simply butadiene, has the formula CH2:CHCH:CH2; it is used in the manufacture of synthetic rubber, latex paints, and nylon and is obtained chiefly by dehydrogenation of butane and butene obtained by cracking petroleum. Chloroprene chloroprene or 2-chloro-1,3-butadiene, colorless liquid organic compound used in the synthesis of neoprene and certain other rubbers. The structure of the chloroprene molecule is very similar to that of isoprene; the molecule contains two double..... Click the link for more information. and isoprene isoprene or 2-methyl-1,3-butadiene , colorless liquid organic compound. It is a hydrocarbon, and is insoluble in water but soluble in many organic solvents; it boils at 34°C;. The isoprene molecule contains two double bonds.
..... Click the link for more information. are the 2-chloro- and 2-methyl-derivatives of 1,3-butadiene; they also are used in the synthesis of rubber.
Butadiene
(also divinyl), an organic compound, CH2=CH—CH=CH2. A colorless gas with a characteristic odor, it has a melting point of -108.9° C, a boiling point of -4.5° C, and a density of 0.650 g/cm3 at -6° C. Butadiene is not readily soluble in water but is in alcohol and kerosene. A mixture of air and butadiene, containing 1.6-10.8 percent butadiene, is explosive. Its flash point is -40° C; the maximum acceptable concentration in air is 0.1 g/m3. Butadiene adds hydrogen, the halogens, hydrogenhalides, and other electrophilic rcegents usually in the 1, 4 positions:
and also maleic anhydride to form the anhydride of tetrahydrophthalic acid (quantitative analysis reaction for determining the presence of butadiene).
Butadiene polymerizes and copolymerizes easily to form valuable elastomers (butadiene rubbers, butadiene-acrylonitrile rubbers, butadiene-styrene rubbers, vinyl pyridine rubbers).
The most promising industrial method of producing butadiene is catalytic dehydration of normal butane and butenes contained in the gases of the oil-refining process and in byproduct gases; the process is carried out in one or two stages. Methods are being developed for the oxidative dehydration of normal butane and butylenes. This will make it possible to substantially increase the yield of butadiene. It is also produced by passing the vapor of ethyl alcohol over a mixed dehydration-dehydrogenation catalyst (the S. V. Lebedev method). Butadiene is a byproduct of the production of ethylene and other olefins of gases formed during the pyrolysis of petroleum products.
REFERENCE
Iukel’son, I. I. Tekhnologiia osnovnogo organicheskogo sinteza. Moscow, 1968.Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
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