Condensations, using chlorosulfonic acid

Dehydrations using chlorosulfonic acid-pyridine (pyridinium sulfamates) provide a convenient synthetic route to amides without die intermediacy of acyl halides. The carboxylic acid was condensed with the amine in pyridine solution containing chlorosulfonic acid at 0-10 °C to give the amides (Equations 9 and 10).2 ... 

A solution of sulfur trioxide [7446-11-9] dissolved in chlorosulfonic acid [7990-94-5] CISO H, has been used as a smoke (U.S. designation FS) but it is not a U.S. standard agent (see Chlorosulfuric acid Sulfuric acid and sulfur trioxide). When FS is atomized in air, the sulfur trioxide evaporates from the small droplets and reacts with atmospheric moisture to form sulfuric acid vapor. This vapor condenses into minute droplets that form a dense white cloud. FS produces its effect almost instantaneously upon mechanical atomization into the atmosphere, except at very low temperatures. At such temperatures, the small amount of moisture normally present in the atmosphere, requires that FS be thermally generated with the addition of steam to be effective. FS can be used as a fill for artillery and mortar shells and bombs and can be effectively dispersed from low performance aircraft spray tanks. FS is both corrosive and toxic in the presence of moisture, which imposes limitations on its storage, handling, and use. 

Both types of wax are readily oxidized (24) and halogenated (116). The latter is an important commercial outlet, the products of which are used as extreme pressure additives for oil (112,113) and as intermediates in Friedel-Crafts condensations (119). Air oxidation leads to carboxylic acids, for which considerable use has been found both here and abroad. Sulfonates can be made by reaction of waxes with chlorosulfonic acid (37,104) or with sulfur dioxide and chlorine (46,99). 

First of all toluene is treated with chlorosulfonic acid to yield/ -toluenesulphonyl chloride, which on treatment with ammonia gives rise to the formation of/ -toluenesulphonamide. The resulting product on condensation with ethyl chloroformate in the presence of pyridine produces N-p-toluenesulphonyl carbamate with the loss of a mole of HCl. Further aminolysis of this product with butyl amine using ethylene glycol monomethyl ether as a reaction medium loses a mole of ethanol and yields tolbutamide. 

Remove the air condenser. In a hood, transfer 0.50 mL of chlorosulfonic acid CISOjOH (MW = 116.5, d = 1.77 g/mL) to the acetanilide in the conical vial using the graduated pipette provided. Reattach the air condenser and drying tube. Allow the mixture to stand for 5 minutes and then heat the reaction vial in the... 

Attach the vial containing the 2,2,2-trifluoroacetanilide (prepared in Experiment [Cl]) to the dry air condenser. Measure, using the 9-in. Pasteur pipet, SLOWLY 0.9 mL of chlorosulfonic acid, and slowly add this reagent to the flask by inserting the pipet down the neck of the air condenser. 

Addition of chlorosulfonic acid (one equivalent) to a solution of / -cresol 127 in carbon disulfide at —15 °C, gave p-tolyl hydrogen sulfate 128 (Equation 41). Reaction of p-cresol 127 with excess chlorosulfonic acid at room temperature yields 2-hydroxy-5-methylbenzene-1,3-disulfonyl chloride 129. o-, m- and p-Cresols were sulfonated by the action of chlorosulfonic acid at 25-105 °C and the isomeric mixture of cresolsulfonic acids by treatment with formaldehyde (2 1) gave condensation products which were useful pharmaceuticals. ... 

Phenols and their simple derivatives react with excess chlorosulfonic acid to give di- and trisulfonyl chlorides consequently it is generally not feasible to prepare the mono-sulfonyl chlorides using this reagent. However, it has been discovered that if the phenol is first converted into the carbethoxy ester, this can be subsequently reacted with excess chlorosulfonic acid, under controlled conditions, to give the mono-sulfonyl chloride. For instance, w-cresol 122 was condensed with ethyl chloroformate in the presence of a base (pyridine) to yield the carbethoxy ester 183, which by treatment with excess chlorosulfonic acid afforded the 4-sulfonyl chloride 184 (Equation 59). 

Attempted chlorosulfonation of 3- and 4-chlorophenylureas failed, presumably as a result of a combination of unfavourable stereoelectronic factors. Sulfonylureas are an important group of highly potent herbicides which may be used for selective weed control in cereals at very low dose rates. Herbicidal (p-sulfamoyl)phenylureas were synthesized from the appropriate phenylureas by mixing them with chlorosulfonic acid at 12-15 C, followed by heating at 60 C and the resultant p-(chlorosulfonylphenyl)ureas were condensed with the amine. °... 

Quinolinesulfonyl hydrazides, useful as blood serum amine monooxidase inhibitors, are synthesised from the parent substituted quinolines via chlorosulfo-nation, achieved by treatment with excess chlorosulfonic acid and subsequent condensation of the sulfonyl chloride with hydrazine. ... 

Phthalocyanines may be regarded as benzopyrrole derivatives, and heating with excess chlorosulfonic acid at 125-130 °C converts them into sulfonyl chlorides. Heating copper phthalocyanine 67 with a mixture of thionyl chloride and chlorosulfonic acid followed by condensation of the resultant product with 3-methoxypropylamine and di(o-methylphenylamino)imine afforded a blue dye used for blue inks in ballpoint pens. Copper phthalocyanine 67, with chlorosulfonic acid and 3-(dimethylamino)propylamine, gave a precipitate which, on dissolution in an aqueous mixture of ethylene glycol-urea and treatment with aluminium sulfate, dyed paper a clear turquoise blue. Crude alpha-type... 

Condensation azo pigments are obtained by reaction of Cl Pigment Red 242 (50 parts) with chlorosulfonic acid (125 parts) and A, A -di-n-butyl-l,3-propanedia-mine (660 parts). The product provides a useful, good-flowing pigment, which may be mixed with other suitable compounds, such as amino-alkyl resins to give gloss paints. ... 

Chlorosulfonic acid may also be used in the manufacture of (amino-alkyl)-phenyl reactive dyes thus the hydroxyethyl sulfone 44 was reacted with chlorosulfonic acid to yield the sulfate 45. The latter was subsequently condensed with cyanuric chloride 46 and the azo-5-pyrazolone 47 to yield the golden-yellow dye 48 (Scheme 10). ... 

Polystyrene foam has been extensively sulfonated by treatment with one or more of the following reagents oleum, chlorosulfonic acid, fluorosulfonic acid or sulfur trioxide. The polysulfonated polystyrenes were useful as shock absorbers in packaging and formed conductive, antistatic, condensation-inhibiting, fire-resistant coatings. - ... 

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. ... 

The sulfo derivatives (10) are used as dispersants for diketopyrrolopyrrole pigments in coatings and plastics. They are manufactured by chlorosulfonation of the diketop)m olopyrrole and subsequent condensation with the appropriate amine. For example, l,4-diketo-3,6-bis(4-biphenylyl)pyrrolo[3,4-c]pyrrole was reacted with chlorosulfonic acid and thionyl chloride to give the sulfonyl chloride which was condensed with 3-(dimethylamino)-l-propylamine to yield the product. The dispersant was used with Cl Pigment Red 264 in the production of a coating (Chapter 8, Section 5). 

The phthalocyanine compound was obtained by chlorosulfonation of a phthalo-cyanine with chlorosulfonic acid-thionyl chloride, followed by condensation of the sulfonyl chloride with an amine to yield the sulfonamide derivative used in the production of the inks (Chapter 6, Section 1.2.7). 

Alkylated sulfonamide groups have proven useful additions to the phenothiazine nucleus. The same seems to hold true in the thioxanthene series. Chlorosulfonation of the benzoic acid, 38, followed by displacement with dimethylamine affords the sulfonamide, 39. This is then taken on to the substituted thioxanthone (41) by the sequence of steps shown above Grignard condensation followed by dehydration gives thiothixine (42). 

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