Hexachloro

Lead lV) chloride, PbCL, is a yellow liquid, m.p. — 15 C, decomposes explosively at lOC C (H2SO4 on (NH4)2PbCU). Yellow hexachloro-plumbales(IV), e.g. (NH4)2PbCl6, are precipitated from the yellow solution resulting from PbOj in cold HCl. 

Hence, if chlorine is passed into a cold suspension (in hydrochloric acid) of lead(II) chloride, lead(IV) chloride is formed. Addition of ammonium chloride gives the complex salt ammonium hexachloro-plumbate(lV) as a yellow precipitate ... 

Dieldrin [60-57-1] or l,2,3,4,10,10-hexachloro-l,4,4t ,5,8,8t -hexahydro-6,7-epoxy-l,4- <7o, Aro-5,8-dimethanonaphthalene (34) (mp 176°C, vp 0.4 mPa at 20°C) is formed from aldrin by epoxidation with peracetic or perben2oic acids. It is soluble in water to 27 / g/L. Aldrin and dieldrin have had extensive use as soil insecticides and for seed treatments. Dieldrin, which is very persistent, has had wide use to control migratory locusts, as a residual spray to control the Anopheles vectors of malaria, and to control tsetse flies. Because of environmental persistence and propensity for bio accumulation, registrations in the United States were canceled in 1974. 

Endrin [72-20-8] is l,2,3,4,10,10-hexachloro-l,4,4t ,5,8,8t -hexahydro-6,7-epoxy-l,4- <7o, <7o-5,8-dimethanonaphthalene (35) (mp 245 dec, vp 0.022 mPa at 25°C) and is soluble in water to 23 / g/L. It is produced by a Diels-Alder reaction of hexachloronorbomadiene with cyclopentadiene, followed by epoxidation. This reaction produces the endo,endo isomer of dieldrin, which is less stable and more toxic with rat LD q values of 17.8 and 7.5 (oral) and 15 (dermal) mg/kg. It is used as a cotton insecticide but because of its high toxicity to fish it has been restricted. 

Hexafluoro-2,5-dihydrofuran [24849-02-3] is distilled into sulfur trioxide [7446-11-9] at 25°C. Addition of trimethyl borate [121-43-7] initiates a reaction which upon heating and distillation leads to a 53% yield of difluoromaleic anhydride. Dichloromaleic anhydride [1122-17-4] can be prepared with 92% selectivity by oxidation of hexachloro-1,3-butadiene with SO in the presence of iodine-containing molecules (65). Passing vaporized... 

Chlorine and bromine add to benzene in the absence of oxygen and presence of light to yield hexachloro- [27154-44-5] and hexabromocyclohexane [30105-41-0] CgHgBr. Technical benzene hexachloride is produced by either batch or continuous methods at 15—25°C in glass reactors. Five stereoisomers are produced in the reaction and these are separated by fractional crystallization. The gamma isomer (BHC), which composes 12—14% of the reaction product, was formerly used as an insecticide. Benzene hexachloride [608-73-17, C HgCl, is converted into hexachlorobenzene [118-74-17, C Clg, upon reaction with ferric chloride in chlorobenzene solution. 

CAS Registry Number Chloro-ben 1,2-Di-chl 1,3-Di-chlor 1,4-Di-chlor 1,2,4-Tri-chl 1,2,3,4-Teti 1,2,4,5-Teti Hexachloro-... 

Benzo[b]thiophene, 6-halo-3-methyl-synthesis, 4, 879 Benzo[6]thiophene, hexachloro-... 

Dibenzo[b,/][l,5]diazocine, tetrahydro-conformation, 7, 704 Dibenzo[b,/][l,4]diazocinediones synthesis, 7, 675 Dibenzodioxin, 2,7-dichloro-toxicity, 3, 992 Dibenzodioxin, hexachloro-toxicity, 3, 992 Dibenzodioxin, octachloro-toxicity, 3, 992... 

GUY LEMAIRE - GUETTE Phenol Chlonnation Regloselective ortho or para halogenation ol phenols and the corresponding ethers (only para) by hexachloro cyciohexadlene 2 or 3 respectively. 

Chlorendic anhydride (l,4,5,6,7,7,-hexachloro-5-norbornene-2,3-dicarboxylic anhydride) [115-27-5] M 370.9, m 234-236 . 235-237 , 238 . Steam distn or recrystn from H2O yields the diacid. The purified diacid yields the anhydride with AC2O. [Prill 7 A/w Chem Soc 69 62 1947.]... 

C2CL6 HEXACHLORO- -142.168 2.9199E-01 -1.8349E-05 -56.82 81 C2H60 ETHYL-ALCOHOL -236.102 2.1904E-01 2.5659E-Q5 -168.28... 

Chemical Designations - Synonyms endo-, exo-, 1,2,3,4,10,10-Hexachloro-l, 4,4a,5,8,8a-Hexahydro-l,4 5,8-Dimethanonaphtalene, HHDN Chemical Formula CuHjCl. ... 

Chemical Designations - Synonyms HEOD endo,exo-l,2,3,4,10,10-Hexachloro-6,7-epoxy-l,4,4a,5,6,7,8,8a-octahydro-l,4 5,8-dimethanonaphthalene Chemical Formula CjjHgCl O. Observable Characteristics - Physical State (as normally shipped) Solid Color Buff to light brown Odor Mild chemical. 

Photochemical brominations offluorobenzene or difluorobenzenes produce hexabromocyclohexane derivatives in low yield. Tri- and tetrafluorobenzenes are unreactive under these conditions [17 (Table 6). Analogous free-radical chlorination of benzotrifluoride produces a 9% yield of the hexachloro adduct [iS]... 

Catalytic reduction of thiophenes over cobalt catalysts leads to thiolane derivatives, or hydrocarbons. " Noncatalytic reductions of thiophenes by sodium or lithium in liquid ammonia leads, via the isomeric dihydrothiophenes, to complete destructions of the ring system, ultimately giving butenethiols and olefins. " Exhaustive chlorination of thiophene in the presence of iodine yields 2,2,3,4,5,5,-hexachloro-3-thiolene, Pyrolysis of thiophene at 850°C gives a... 

Figure 2.17 Schematic representation of the set-up used for on-line liquid-liquid exti action coupled with capillary GC when using a membrane phase separator. Reprinted from Journal of High Resdution Chromatography, 13, E. C. Goosens et al., Determination of hexachloro-cyclohexanes in gi ound water by coupled liquid-liquid extraction and capillaiy gas cliro-matography , pp. 438-441, 1990, with permission from Wiley-VCH.

Aldrin, a chlorinated insecticide now banned for use in the United States, can be made by Diels-Alder reaction of hexachloro-l,3-cyclopentadiene with norbomadicne. What is the structure of aldrin ... 

Polychlorination processes have included exhaustive chlorination in the presence of antimony pentachloride, which destroyed the molecule (1882JCS412). Chlorine in carbon tetrachloride gave 3,4,6,8-tetrachlo-roquinoline chlorine dissolved in thionyl chloride gave the 4,5,7,8-isomer, whereas thionyl chloride alone produced a mixture of 3,4,5,6,7,8-hexachloro- (57%) and 3,4,6,8-tetrachloro- (37%) quinolines (73YZ73 74S356, 74URP432143). 

Bismuth, tris(dipropyldithiophosphonium)-stereochemistry, 1, 81 Bismuthate, hexabromo-structure, 1,73 Bismuthate, hexachloro-structure, 1, 73 Bismuthate, hexaiodo-structure, 1, 73... 

Iridium, carbonylchlorobis(triphenylphosphine) solid state reactions with hydrogen chloride, 1, 470 Iridium, dihalodicarbonyl-, 6, 142 Iridium, hexachloro-catalysts... 

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