Chlorobuta- 1/2-diene

Culik R, et al P-Chloroprene (2-chlorobuta-diene-1,3) embryotoxic and teratogenic studies in rats (abstr no 194). Toxicol Appl Pharmacol hi 12, 1976... 

The monomer, 2-chlorobuta-1,3-diene, better known as chloroprene, is polymerised by free-radical emulsion methods to give a polymer which is predominantly (-85%) fr<2 s-l, 4-polychloroprene but which also contains about 10% cii-1,4- 1.5%, 1,2- and 1% of 3,4-structures (Figure 11.17). The commercial polymers have a Tg of about -A3°C and a of about 45°C so that at usual ambient temperatures the rubber exhibits a measure of crystallinity. 

Synonyms CCRIS 873 Chlorobutadiene 2-Chlorobutadiene-l,3 2-Chlorobuta-1,3-diene 2-Chloro-1,3-butadiene p Chloroprene EINECS 204-818-0 Neoprene NSC 18589 UN 1991. 

Chlorobenzamine, see 4-Chloroaniline p-Chlorobenzamine, see 4-Chloroaniline Chlorobenzol, see Chlorobenzene 2-Chlorobenzylidenemalononitrile, see o Chlorobenzylidenemalononitrile 2-Chlorobmn, see o-Chlorobenzylidenemalononitrile Chlorobromoform, see Dibromochloromethane Chlorobromomethane, see Bromochloromethane Chlorobutadiene, see Chloroprene 2-Chlorobutadiene-l,3, see Chloroprene 2-Chlorobuta-l,3-diene, see Chloroprene... 

Vinyl chloride and chloroprene (2-chlorobuta- 1,3-diene) are among the major intermediates which are produced industrially on the 100,000 tonnes/year scale by thermal chlorination or oxychlorination of ethylene or butadiene. 

SYNS 2-CHLOOR-L3-BUTADIEEN (DUTCH) 2-CHLOR-1.3-BUTADIEN (GERMAN) CHLOROBUTADI-ENE 2-CHLOROBUTA-1,3-DIENE 2-CHLORO-l,3-... 

CHLOROBUTA-l,3-DIENE see NCI500 2-CHLORO-l,3-BUTADIENE see NCI500 2-CHLOROBUTANE see CEU250... 

Diphenyldiazomethane decomposition in the presence of a diene has been reported to result in monoadduct formation. When 2-chlorobuta-l,3-diene and 1,1-dicyclopropylbuta-l,3-diene are used, attack takes place exclusively at the less-substituted double bond. The products, l-(l-chlorovinyl)-2,2-diphenylcyclopropane (5), ° and 2-(2,2-dicyclopropylvinyl)-l,l-diphe-nylcyclopropane (6), ° respectively, were obtained in good yield. 

Allyl sulfides do not form cyclopropanes when they react with dichlorocarbene. Instead, the sulfonium ylide undergoes a [2,3] sigmatropic rearrangement to give a 1,1-dichloro derivative, which affords 1-alkylsulfanyl-l -chlorobuta-1,3-diene 4 after elimination of hydrogen chlor-ide.2 ... 

Dichlorocyclopropanation of allylsilanes, mono- or disubstituted at C3, afforded 1,1-dichloro-2-trimethylsilylcyclopropanes which were treated with cesium fluoride in dimethylformamide to give derivatives of 3-chlorobuta-l,3-diene. 

Similar conversions were reported with 1,2,3,4,5-pentamethylcyclopenta-l,3-diene, to give stereoselectively the ent/o-6-phenyl-e.vo-4-methyl isomer of pentamethylphenylbicy-clo[3.1.0]hex-2-ene with > 85% yield.Benzylidene transfer to (Z)- and ( )-penta-l,3-diene, isoprene and 2-chlorobuta-l,3-diene regioselectively occurred at the more electron-rich C-C double bond to give trans- and cw-phenylvinylcyclopropanes. The transjcis ratio ranged from 0.52 to 2.2. 

The scope of the normal Michaelis-Arbuzov procedure in the synthesis of polyunsaturated phosphonic acids has not been widely explored, but it has been reported that 2-chlorobuta-1,3-diene and triethyl phosphite react together to give about 10% of the ester 220. ... 

The chlorination of (3-chlorobuta-l,3-dien-2-yl)phosphonic diesters (136) proceeds by 1,4-addition, the products being identical with those derived from the phosphonic dichlo-... 

The diene component of the monomer mixtures from which rubbers of types (2)-(4) are produced is either butadiene (strictly buta-1,3-diene) (I) or the butadiene derivative 2-chlorobuta-1,3-diene (II), commonly known as chloroprene. 

Chlorobromodifluoromethane. See Bromochlorodifluoroemethane Chlorobromomethane. See Bromochloromethane Chlorobufam. See Chlorbufam Chlorobutadiene 2-Chlorobutadiene 2-Chloro-1,3-butadiene 2-Chlorobuta-1,3-diene 2-Chlorobutadiene-1,3 P-Chlorobutadiene. See Chloroprene... 

Chlorobuta-1,3-diene 2-Chlorobutadiene-1,3 P-Chlorobutadiene 2-Chloroprene p-Chloroprene... 

Butadiene is chlorinated in the gas phase to give mixtures of 1,2-dichlorobut-3-ene and l,4-dichlorobut-2-ene, which are interconvertible in the presence of copper catalysts. The former is dehydrochlorinated by contact with aqueous sodium hydroxide, to give chloroprene (2-chlorobuta-l, 3-diene) for polymer production (neoprene). The earlier acetylene-dimer route has been phased out. U.S. production of neoprene has fallen to about 120 kt per annum, of which over 40% is exported European production is somewhat lower. 

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