Sulphon chlorides

The potassium benzenesulphonate is carefully dried on the water-bath, powdered, and mixed with the phosphorus pentachloride in a flask. A vigorous reaction sets in. When it hats abated, the flask is heated on the water-bath for one hour, and the mass occasionally stirred with a glass rod. The product is poured into a flask containing 200 c.c. cold water and allowed to stand an hour. The sulphonic chloride, which separates as an oil, is then extracted with ether, dehydrated over calcium chloride, decanted, and the ether removed on the water-bath. Yield, 10 grams of a light brown oil. 

Reaction.—i. Grind up in a mortar i c.c. of sulphonic chloride with 5 grams powdered ammonium carbonate, and leare on the water-bath until the smell of the sulphomc chloiide has gone. Add water, filter, and wash, and crystallise the residue of benzene sulphonamicle from spirit, CqHjSO.CI -f 2NH4HCOJ = CoHr,SO,jNHo + 2H20- -2CO,-fNH,Cl. 

Add I c.c. of the sulphonic chloride to 2 c.c. aniline, stir up well, add water, and acidify with a few diops of concentrated HCl (methyl violet paper). Filter, wash, and crystallise the benzenesulphonanilide from spirit, C(jH3SO,Cl- -NH,C(,H- -= QHoSO NHC.H -l-HCl. 

Add 2 c.c. absolute alcohol to i c.c. sulphonic chloride and excess of caustic soda until alkaline warm gently for fire minutes and add more caustic soda if necessary. Cool, and extract with ether. The residual liquid consists of benzene ethyl sulphonate, CoH SOjCl + HOC Hj = CcH SOoOC H -p HCl. 

On reihieiion of the sulphonic chloride with zinc dust. and u.ilei, tlie zini s.dt of the snlphinl( u id is foimcd,... 

Presumably less nucleophilically assisted solvolyses could show higher a-deuterium isotope effects, and there is a linear relationship between the magnitude of nucleophilic solvent assistance (Table 2) and the a-deuterium isotope effect for solvolyses of 2-propyl sulpho-nates (Fig. 7). Another measure of nucleophilic assistance is the ratio k2 (OH )/, where k2 is the second-order rate constant for nucleophilic attack by OH and kx is the first-order rate constant for reaction with the solvent water, and a linear correlation was obtained by plotting the ratio versus the experimentally observed isotope effects for methyl and trideuteriomethyl sulphonates, chlorides, bromides and iodides (Hartman and Robertson, 1960). Using fractionation factors the latter correlation may also be explained by a leaving group effect on initial state vibrational frequencies (Hartshorn and Shiner, 1972), but there seems to be no sound evidence to support the view that Sn2 reactions must give a-deuterium isotope effects of 1-06 or less. 

In the presence of oxidising agents, the sulphur atom is oxidised and the perchloromethyl mercaptan is converted into trichloromethyl sulphonic chloride, CCI3—SOj—Cl. 

Benzenesulphonyl - p - arsanilic acid, CgH6.SO2.NH.CeH4. AsO(OH)2.—This add may be obtained either from p-arsanilic add and benzene sulphonic chloride by the Schotten-Baumann reaction, or from benzenesulphonyl-p-aminophenylamine by Bart s reaction. The sodium salt goes under the name of Hectine and the mercury salt is Hectargyre. 

The acid crystallises in pale yellow prisms, which do not melt on heating, but explode. It is soluble in alcohol, acetone, acetic add, and ethyl acetate, fairly soluble in hot water, sparingly soluble in cold water. The disodium salt is orange and has a neutral reaction in water, whilst the trisodium salt is alkaline to litmus and neutral to phenolphthaldn. The add condenses with p-toluene sulphonic chloride in alkaline solution, yielding glistening plates, M.pt. 171° C. 

Sulphon Chlorides.—(2) Reaction with phosphorus penta-chloride. As sulphonic acids contain the acid hydroxyl group, they undergo the characteristic reaction with chlorides of phosphorus and exchange the hydroxyl for chlorine. The product is known as a sulphon chloride. 

Sulphon Amides.— Just as acetyl chloride is converted into acetamide by the action of ammonia so benzene sulphon chloride yields benzene sulphon amide by the same treatment. 

These two reactions by which a sulphonic acid is converted first into the sulphon chloride and then into the sulphon amide may be applied with considerable ease to all sulphonic acids. The sulphon chloride reacts further with phosphorus penta-chloride all of the sulphur... 

As sulphuric acid by reduction yields sulphurous acid so the sulphonic acids by reduction yield sulphinic acids. The action takes place better, however, if instead of a sulphonic acid we use the corresponding sulphon chloride. When benzene sulphon chloride is treated with zinc the zinc salt of the benzene sulphinic acid is obtained. zCeHs—SO2CI + Zn ------------------- (C6H6S02)2Zn + ZnCl2... 

Salts of thio-sulphonic acids are also prepared by treating sulphon chlorides with metallic sidphides e.g. K2S. 

They may also be made from sulphon chlorides by treating with a hydrocarbon or a halogen derivative, in the presence of AICI3. 

By means of this last reaction and using in one case benzene sulphon chloride and toluene, and in the second case toluene sulphon chloride and benzene, exactly the same phenyl tolyl sulphone is formed. 

With chloroacetyl chloride it gives the chloroacetic ester of chloromethyldicthylcarhinol, CH2Ci.C(C3H5)2.0.C0.CH2Cl with butyryl chloride it forms hexanom(3) with benzoyl chloride, ethyl phenyl ketone is obtained, and with benzene sulphonic chloride, the main product is zinc benzene sulphinate and a little sulphone. 

Dry chlorine gas, hypochlorous acid, thallic chloride, silicon tetrachloride, stannic chloride, zirconium tetrachloride, phosphorus trichloride, mercurous chloride, thionyl chloride, benzene sulphonic chloride, benzal chloride,phenyl iododichloride. ... 

In the sulphonamides, in consequence of the strongly negative character of the X.SO,-group. the hydrogen of the amido-group is so easily replaced by metals, that they dissolve in water solutions of the alkalies to form salts of the amide. (Try it) If a sulphon-chloride is allowed to stand a long time with an aliphatic alcohol, a sulphonic add ester is formed, eg. ... 

T richloromethyl-sulphonic chloride T richloromethyl-sulphonic acid Dichloromethyl-sulphonic acid Chloromethyl-sulphonic acid Methylsulphonic acid... 

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