Poly sulfur-aluminum chloride

Katsuya et al. [5 published the oxidative coupling (agent copper(II) chloride/ aluminum chloride) of electron-rich benzene derivatives such as 2,5-dimethoxy-benzene to poly(2,5-dimethoxy-1,4-phenylene) (2). The resulting polymer is only soluble in concentrated sulfuric acid, and is fusible at 320r C. Ueda et al. 16] described the coupling of the same monomer with iron(III) chloride/aluminum chloride. The polymers obtained by the authors were not thoroughly para-linked. 

TP here are very few examples in the literature of poly (arylene polysulfides). Perhaps the first such preparation was that of Fried el and Crafts (I), in which benzene reacted with sulfur in the presence of aluminum chloride. Within the last 15 years, several poly(arylene polysulfides) have been prepared by related reactions in which various aromatic compounds reacted with sulfur monochloride in the presence of Friedel-Crafts catalysts (2, 3, 4). A variation of this reaction has also been reported using a bifiunctional sulfenyl chloride (5) ... 

Other Lewis acid/oxidant systems have been employed including ASFj/AsFj [100] and liquid SO2 or sulfuric acid and aluminum chloride [101]. Poly(paraphenylene) has been synthesized by the electrochemical oxidation of benzene in solvents such as liquid SO2 [102] and concentrated sulfuric acid [103], or with the addition of Lewis acids including aluminum chloride [104], CuCl2/LiAsFg [105], and BF30Et2 [106], affording polymeric films. To improve the solubility, poly(paraphenylene) has been sulfonated [107] and alkylated [108] with propyl halides to give materials with enhanced solubility. 

When polystyrene is sulfonated in chlorinated hydrocarbons with a complex of dioxane-SOs, the polymer precipitates from solution at low concentrations. Complexes of ketones with SO3 can also be used to sulfonate polystyrene in halogenated solvents. The ratio of sulfonation is more favorable for poly(vinyl toluene) than it is for polystyrene at the same conditions. Also, sulfur dioxide swells polystyrene. The polymer can be sulfonated in this medium with sulfur trioxide or with chlorosulfonic acid. Polystyrene, sulfonated in CS2 with aluminum chloride catalyst, is water insoluble in a free acid form. ... 

Creative reading of the literature has led to allegations that poly-(phenylene sulfide) (PPS) is a very old polymer that was prepared first by Friedel and Crafts in 1888 from benzene and sulfur in the presence of aluminum chloride (A1C1 ). These allegations have become entrenched in the liter-... 

Poly[isobutylene-co-isoprene] or butyl rubber was synthesized in 1937 at the Standard Oil Development Co., forerunner of ExxonMobil Chemical Co. (2). The first sulfur-curable copolymer was prepared in ethyl chloride over an aluminum chloride catalyst with 1,3-butadiene as the comonomer however, it was soon found that isoprene was a better comonomer and that methyl chloride was a better polymerization diluent. During World War II, the natural rubber supply to the United States was drastically curtailed, boosting the production of synthetic rubber. The commercial production of butyl rubber in 1943 was an enormous scientific and engineering achievement given the very early state of the art and complexity of this technology. 

Poly(p-lithiostyrene), a highly reactive polymer prepared from iodinated polystyrene and lithium, yielded a copolymer containing 62 mol-% p-mercaptostyrene when sulfur was added 61). Similarly, treatment of styrene-divinylbenzene copolymers with sulfur and aluminum chloride yielded sulfur-containing polymers in which 21 % of the incorporated sulfur is present in the form of mercaptan groups (62). 

The mechanism of the formation of (I) and (II) by debenzylation reaction was interpreted by Fles et al [3] as follows When one mole of aluminum halide is used it ionizes the covalent carbon-chloride bond and forms an ion pair (III) in which for steric reasons the CO residue cannot get close enough to its own sulfur to debenzylate it as easily as it can approach and debenzylate the sulfur of another molecule, thus forming poly-thiol-ester (II). 

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