Diphenyl ether- 1,4 -disulfonyl 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. 

In 1967 3M introduced polybiphenyldisulfones under the Astrel 360 trade name. This polymer was made by the Friedel-Crafts reaction of biphenyl-4,4 -disulfonyl chloride with diphenyl ether and exhibited a very high Eg of 277°C [26]. The structure is shown in Fig. 1.12. The price was very high, it was difficult to melt process, and had limited availability. This resin is no longer commercially available. 

Ethylene- and trimethylene-glycol diphenyl ethers 192 and 193 reacted with excess chlorosulfonic acid in chloroform to give the 4,4 -disulfonyl chlorides 194 and 195 respectively (Equation 62). 

Di(acylamido) diphenyl ethers are similarly chlorosulfonated by treatment with excess reagent in cold carbon tetrachloride thus 4,4 -diacetamidodiphenyl ether afforded the 3,3 -disulfonyl chloride (85%). ... 

The cyclization of diphenyl ether 206 to the cyclic sulfone derivatives 208 and 209 achieved by prolonged heating with a large excess of the reagent is analogous to similar reactions observed with biphenyl and the diphenyl alkanes (see Section 2, pp 42 and 40). 4-Bromodiphenyl ether by treatment with excess chlorosulfonic acid (two equivalents) at 25-30 °C afforded the 4-sulfonyl chloride (45%). In this molecule, the other reactive 4-position is blocked by the bromine atom. In contrast, with diphenyl ether 206 all attempts to obtain the monosulfonyl chloride by reaction with chlorosulfonic acid failed, and the only isolated product was the 4,4 -disulfonyl chloride. In the case of 4,4 -dibromodiphenyl ether, in which... 

These sulfone polymers e.g. 53) may also be prepared by polysulfonation of diphenyl ether 54 with the corresponding 4,4 -disulfonyl chloride 55 (Equation 7). 

The chemistry of sulfonyl hydrazides and azides has been discussed and both derivatives are used as blowing and cross-linking agents in the manufacture of foam rubbers and plastics. Some of the best hydrazides for this purpose are diphenyl ether-4,4 -disulfonyl hydrazide 59 together with the corresponding thio analogue 60. These hydrazides are respectively prepared by reaction of diphenyl ether or diphenyl sulfide with excess chlorosulfonic acid as previously described (Chapter 4, p 74, 76), followed by condensation of the appropriate disulfonyl chloride with excess hydrazine hydrate. ... 

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