Aryl sulphonyl chlorides

C.H.[0].S.Halogen Aryl sulphonyl chlorides C.H.[0].N.S Salts of amines and nitro- ... 

Procedure 1. Dissolve 1 g. of the compound in 5 ml. of chloroform in a test-tube and cool in ice. Add 5 ml. of chlorosulphonic acid CA UTION in handhng) dropwise and with shaking. When the initial evolution of hydrogen chloride subsides, remove the reaction mixture from the ice and, after 20 minutes, pour it into a 50 ml. beaker filled with crushed ice. Separate the chloroform layer, wash it well with water, and evaporate the solvent. Recrystallise the residual aryl sulphonyl chloride from light petroleum (b.p. 40-60°), chloroform or benzene this is not essential for conversion into the sulphonamide. 

Procedure 2. Follow Procedure 1 except that no solvent is employed. Pour the s3Tupy reaction mixture on to crushed ice, remove the resulting aryl sulphonyl chloride and/or sulphone, if a sohd, by filtration with suction and, if a hquid, by means of a small separatory funnel or dropper, and wash with water. 

To convert the aryl sulphonyl chloride into the sulphonamide, use either of the following methods —... 

The aryl sulphonyl chlorides may also be obtained from the aromatic hydrocarbon and chlorosulphonic acid, for example ... 

These two classes of compounds can be prepared by treating diphenyl disulphide and aryl sulphonyl chlorides with sodium telluride followed, respectively, by a-halocarbonyl compounds and alkyl halides. 

Acid chlorides. The corresponding acid and hydrogen chloride are the most likely impurities. Usually these can be removed by efficient fractional distillation. Where acid chlorides are not readily hydrolysed (e.g. aryl sulphonyl chlorides) the compound can be freed from contaminants by dissolving in a suitable solvent such as alcohol-free chloroform, dry toluene or petroleum ether and shaking with dilute sodium bicarbonate solution. The organic phase is then washed with water, dried with sodium sulphate or magnesium sulphate, and distilled. This procedure is hazardous with readily hydrolysable acid chlorides such as acetyl chloride and benzoyl chloride. Solid acid chlorides are satisfactorily crystallised from toluene, toluene-petroleum ether, petroleum ethers, alcohol-free chloroform/toluene, and, occasionally, from dry ethyl ether. Hydroxylic or basic solvents should be strictly avoided. All operations should be carried out in a fume cupboard because of the irritant nature of these compounds. 

Arylsulphonyl 1,2,4-triazolides (35), prepared from the appropriate aryl-sulphonyl chloride and IjH-1,2,4-triazole, can be used to activate phospho-monoesters or -diesters for condensation reactions in polynucleotide synthesis. Yields for condensations involving guanosine residues are better than those obtained using aryl sulphonyl chlorides. 

Aryl sulphonyl chlorides may also be synthesized from the sulphinyl chloride, by oxidation with chlorine, in 80% yield573 (equation 146) or dimethyl sulphoxide574. Sulphinate esters may also be utilized as the precursor to sulphonyl halide via oxidative halogenation. For example, methyl methanesulphinate is converted to methanesulphonyl chloride in excellent yield at 0°C568. 

Condensation of A -benzyloxycarbonylaminomethanephosphoric acid with 2, 3 -0-isopropylidene nucleosides in the presence of an aryl sulphonyl chloride gives the corresponding phosphonates, which on treatment with aqueous hydrobromic acid lead to the nucleotide analogues (10). Although (10) are resistant to alkaline phosphatase, they are degraded slowly by snake venom 5 -nucleotidase. Uridine 5 -phosphofiuoridate is also degraded slowly by the latter enzyme whereas it is resistant to the former. ... 

Protection of a dinucloside phosphate by reaction with trichloroethanol and an aryl sulphonyl chloride only takes place with rather low yield [32]. 

Commonly used organic electrophiles involve C(sp ) hybridized carbon as coupling partners like in acid chlorides, (hetero)aryl halides (Cl, Br, I) and triflates, alkenyl halides and triflates activated C(sp ) hybridized carbon like allyl halides and acetates, benzyl halides are also used. Recently the use of unactivated alkyl halides has also been reported. Aryl sulphonyl chlorides and arenediazonium salts have also been used as organic eletrophiles. 

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