Benzene-1,4-disulfonyl chloride

The commercial synthesis of poly(phenylenes) starts with a mixture of 0-, m-, and p-terphenyl (subsequently referred to as Ar). The mixture is converted to chloroform-soluble prepolymers with m-benzene disulfonyl chloride. The arylation reaction consists of a thermal degradation reaction of the sulfonyl chloride in the presence of terphenyls. Presumably, this involves a free radical process, and not a Friedel-Crafts reaction ... 

After removal of ether on the steam bath, the residual 5-chloroaniline-2,4-disulfonyl chloride, which may be crystallized from benzene-hexane MP 130° to 132°C, was cooled in an ice bath and treated with 150 ml of 2B% ammonium hydroxide in a 2-liter Erlenmeyer flask. The mixture was heated on the steam bath for 1 hour, cooled and the product collected on the filter, washed with water and dried. Upon crystallization from dilute alcohol 5-chloro-2,4-disulfamylaniline was obtained as colorless needles, MP 251° to 252°C. 

Toluene-3,4-dithh>l. l,2-Dimercapto-4-methyl-benzene dithiol . C7H8S, mol wt 156-27. C 53.80%. H 5.16%. S 41-04%. Prepd from toluene-3.4-disulfonyl chloride with tin and hydrochloric add Mills, Clark, J. Chem. Soc. 1936, 178. 

Benzene-l,4-disulfonyl chloride 5,8-Dichloronaphthalene-2-sulfonvl chloride... 

Various synthetic approaches have been demonstrated for the synthesis of PAEs since early days [35 0], PAEs were synthesized by Ullmann condensation between bisphenols and aryl fcis-halide monomers using Cu(I) salt/pyridine as catalyst [36], General Electric developed the first commercially successful PAE poly(2,6-dimethyl phenylene oxide) (PPO) [38], It was prepared by oxidative coupling of 2,6-dimethyI phenol. However, this process has its own restrictions, because it does not allow much structural variation or inclusion of any electron-withdrawing group into the polymer main chain. First attempts to synthesize polysulfones (PSF) were successfully done by Friedel-Crafts sulfonylation reaction of arylenedisulfonyl chlorides, for example, diphenyl ether-4,4 -disulfonyl chloride with diaryl ethers, for example, diphenyl ether, or by self-condensation of 4-phenoxy benzene sulfonyl chloride in the presence of FeCls [41], Whereas the former reaction involves side reactions (sulfonylation not only in the para- but also in the ort/io-position), the latter produces only the desired linear all-para products. 

When benzene is heated with a large excess of chlorosulfonic acid ( 10 equivalents) at 150-160 °C (2 hours), the major product is benzene- n-disulfonyl chloride. 

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