Chlorobenzene, chlorosulfonation

Chlorosulfonation of chlorobenzene under milder conditions iffords the product of monosubstitution (166) reaction with... 

Bromine (dry gas) Bromine (liquid) Bromobenzene Butanol Butyl acetate Butylamine Butylchloride Butyric acid Calcium chloride Carbon tetrachloride Castor oil Cellosolve Cellosolve acetate Chlorine (dry gas) Chlorine water Chloroacetic acid Chlorobenzene Chloroform Chlorosulfonic acid Chromic acid Citric acid Colza oil Copper sulfate Cyclohexane Cyclohexanol Cyclohexanone... 

Sixty grams (0.52 mole) of chlorosulfonic acid is cooled to —15° and agitated while 20 g. (0.18 mole) of chlorobenzene is added drop-wise over a period of 2 hours. The temperature is held in the range — 5° to —10° during this operation and for an additional 2 hoxirs. After standing at room temperature for 12 hours, the mixture is... 

Pyrolysis products of chlorinated polyethylene contain molecules similar to those found in polyethylene pyrolysates and, in addition, compounds similar to that obtained from vinyl chloride (significant amount of HCI). Chlorosulfonated polyethylene typically contains only about 1.5% sulfur, but sulfur-containing compounds such as SO2 can be detected among its pyrolysis products. The distribution of chlorine atoms in chlorinated polyethylene has been investigated using Py-GC [55, 56]. The polymer was considered equivalent with a terpoiymer poly[ethylene-co-(vinyl chloride)-co-(1,2-dichloroethylene)]. The level of specific degradation products such as aromatic molecules (benzene + toluene + styrene + naphthalene), chlorobenzene, and dichlorobenzenes correlates well with the carbon/chlorine ratio in the polymer. 

Sulfonylureas, e.g. chlorsulfuron (69), are an important group of herbicides which will selectively control many broad-leaved weeds in cereals at remarkably low doses ( 20g/ha 1 lha = 104m2). Chlorsulfuron (69), can be synthesised from chlorobenzene by treatment with chlorosulfonic acid, which yields a mixture of the o-and -sulfonyl chlorides. The desired o-sulfonyl chloride (79) is separated... 

When the product of reacting chlorobenzene and chlorosulfonic acid is aminated under pressure, the product is dapsone (32), used in control of leprosy75. This sulfone was developed as a result of sulfonamide studies undertaken at Bayer that include thiosemi-carbazones active against tuberculosis. 

Monomers. Bis ( 4-chlorophenyl ) sulfone. We prepared bis (4-chlorophenyl)sulfone (I in Reaction 1) by dropwise addition of chloro-sulfonic acid (0.4 mole) to chlorobenzene (0.2 mole) at 0°C. One hour after the chlorosulfonic acid addition was completed, an additional quantity of chlorobenzene (0.16 mole) was added to the cold solution. 

The industrial manufacture of DDT is based on the synthesis described by Zeidler. Chloral, chloral alcoholate or chloral hydrate is reacted with chlorobenzene in the presence of sulfuric acid, oleum or chlorosulfonic acid (Rueggeberg and Torrance, 1946). The t hnical product thus obtained contains several impurities, including the ortho-para (2) and ortho-ortho (3) isomers, 2,2-bis-(p-chlorophenyl)-1,1 -dichloroethane (p,p -DDD, 4), its ortho-para isomer (o,p -DDD,... 

In contrast to the reaction of bromob enzene with sulfuric acid, which requires a high temperature and yields a mixture of products (p. 148), the reaction with oleum or with chlorosulfonic acid in carbon disulfide solution is normal and gives the 4-sulfonic acid and bis-(4-bromo-phenyl) sulfone. The 4-sulfonic acid is sulfonated in the 2-position by either pyrosulfuric acid or sulfur trioxide the reaction with oleum at high temperatures is abnormal, like that of chlorobenzene, and yields the 3,5-disulfonic acid. 

Barium chloride Barium salts, aqueous Carbonic acid Castor oil Chlophen A 60 Chloral hydrate, aqueous Chloramine, aqueous Chloride of lime, aqueous Chlorine, wet + dry Chloroacetic acid Chlorobenzene Chloroform Chloromethyl o-Chloronaphthalene Chloroprene Chlorosulfonic acid Chromic acid Citric acid... 

In this work, toluene was observed to be five times more reactive than benzene. In the sulfonation of benzene, toluene and chlorobenzene by chlorosulfonic acid (just more than one molar equivalent) in dichloromethane or nitromethane, the major products were the corresponding arylsulfonic acids with only small amounts of the sulfones and sulfonyl chlorides. ... 

Kinetic and product studies were carried out on the reactions in dichloromethane for the reaction of chlorobenzene with chlorosulfonic acid, the electrophilic species was probably CIS2O6H. In the analogous reaction with benzene, unlike chlorobenzene, there was an induction period in the sulfonation. The sulfonating entity for the main reaction was concluded to be PhS206H.ClS03H, whereas for the initial reaction the electrophile was the same as for chlorobenzene, namely CIS2O6H. The sulfonation therefore may proceed as shown in Equations 35 and 36, in which the formation of the a-complex is the rate-decisive step. 

Anisole (methyl phenyl ether) is extremely reactive towards sulfonation due to the presence of the strongly electron-donating (-fM) methoxy group. It therefore reacts with chlorosulfonic acid (two equivalents) at 0 °C to give mainly p-methoxybenzenesulfonyl chloride. With chlorobenzene, the chlorine atom exerts a strong electron-withdrawing (-1 effect) so sulfonation will be rather less easy than for benzene. Treatment of chlorobenzene with chlorosulfonic acid (four equivalents) at 25 C (3 hours) afforded p-chlorobenzenesulfonyl chloride (84%) and di(/7-chlorophenyl sulfone) (6%)." Chlorobenzene with chlorosulfonic acid (six equivalents) at 150-160 °C (8 hours) gave the 2,4-disulfonyl chloride. 

Chlorobenzene reacts with an equimolar amount of chlorosulfonic acid to give mainly the p-sulfonic acid together with a little of the sulfonyl chloride and the sulfone. With an excess of the reagent good yields of p-chlorobenzenesulfonyl chloride are obtained. The kinetics of the sulfonation of chlorobenzene with chlorosulfonic acid have been studied, and the reaction has been reported in several patents. These involved various modifications such as the use of excess reagent in hydrocarbon solvents containing alkali metal or ammonium salts, or a mixture of the reagent with thionyl chloride in the presence of sulfamic acid, sodium sulfate or dimethylformamide. In the reaction, the yield of 4,4 -dichlorodiphenyl sulfone can be increased under a variety of conditions the... 

Chlorobenzene, by prolonged heating with excess chlorosulfonic acid, gives the 2,4-disulfonyl chloride. ... 

In 1982, DuPont introduced the sulfonylurea herbicides which are effective at remarkably low dose rates an important example is chlorsulfuron 22 used for selective control of broad-leaved weeds in cereals at rates of 10-40 gha this herbicide can be prepared from chlorobenzene 21 (Scheme 5) (see also Chapter 6, ref 33), The first stage of the synthesis, namely the reaction of chlorobenzene with chlorosulfonic acid yields a mixture of the o- and / -sulfonyl chlorides, which may be separated by fractional distillation, since the o-isomer has the lower bp (Chapter 6, ref 33). 

Benzene, toluene and chlorobenzene were also alkylated by C1-C3 alkyl sulfates in the presence of chlorosulfonic acid catalyst, which proved the intermediacy of alkyl sulfates in alkylation of benzenes by alkenes-chlorosulfonic acid mixture. Diisopropyl sulfate showed strong alkylating properties only in the presence of chlorosulfonic acid. 

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