Sulphamides, acidity

Both compounds are soluble in water and are readily hydrolysed to sulphamic acid, HjN S03" andammonia the hydrogen atoms are in each case replaceable by metals to form salts. Many derivatives of sulphamide and cyclic derivatives of sulphimide are known. 

When cyclic sulphamides (18 and 19) were studied148, it was found that the six-membered rings are more acidic than their acyclic analogues by ca 2.5 pKa units and that the five-membered cyclic sulphamides are ca 4 pK units more acidic than the model open-chain counterparts. 

The nitration is carried out with a large excess of anhydrous nitric acid (10 parts of acid to 1 part of sulphamide). The product is precipitated by pouring the nitric acid solution into water. 

As will be seen by comparing the formulie of sulphuric acid, S02(OH)2, and sulphamide, S02(NH2)2, hydroxylamineisosulphonic acid is the amide corresponding with permonosulphuric acid, although it has not been directly prepared from this acid. In agreement with this relationship, however, hydroxylamineisosulphonic acid or amidopermonosulphuric acid possesses marked oxidising properties, readily liberating iodine from potassium iodide. 

Sulphamide, SOa(NH2)2, the amide of sulphuric acid, may be obtained by the action of dry ammonia upon a cooled solution of sulphury chloride in either ethylene chloride or chloroform solution 1... 

In the pure state, sulphamide is a non-electrolyte, indicating the weakness of its acidic tendencies. With the alkalis it forms salts, but not more than two atoms of hydrogen are displaceable by the metal.4... 

Imidodisulphamide, NH2.S02.NH.S02.NH2, is the first product of the action of ammonium carbamate on pyrosulphuryl chloride.2 It is also obtained when sulphamide is heated nearly to its melting-point. Imidodisulphamide forms needle-shaped colourless crystals, melting at 160° C., and having a distinctly acid taste, since water causes rapid decomposition into sulphamide and amidosulphonic acid ... 

Sulphimide, or Trisulphimide, (S02NH)s.—This is formed together with ammonia and imidosulphonic acid when sulphamide is heated at 200° to 210° C. It is also formed in small quantity as the ammonium salt, together with sulphamide, when sulphuryl chloride is treated with ammonia in chloroform solution 4... 

According to A. Loir and C. Drion, when liquid ammonia at —65° is poured on to cone, sulphuric acid, the liquids do not mix, and a reaction gradually sets in. According to V. A. Jaquelain anhydrous ammonia reacts with sulphuric acid, forming sulphamide, and, according to A. Woronin, ammonium amidosulphate. 

Well-cooled sulphuryl chloride, diluted with 15-20 vols. of chloroform, is sat. with dry ammonia, the precipitated product dissolved in water, the soln. acidified with nitric acid, and the whole of the chlorine precipitated with silver nitrate the filtered soln. is neutralized with alkali, treated with silver nitrate, and the crystalline precipitate, which consists of silver sulphimide and some other silver derivative, separated by filtration. After adding a further quantity of silver nitrate, the clear soln. is treated with alkali, when silver sul-phamide is obtained as a colourless, amorphous precipitate, which, however, is invariably mixed with some other silver compound, probably the same as that present in the silver sulphimide precipitate. In order to remove this impurity, the well-washed precipitate is treated with hydrochloric acid in quantity exactly sufficient to convert the silver into chloride, and the strongly acid soln. is neutralized with ammonia and mixed with silver nitrate, when only the silver compound of unknown composition is precipitated pure silver sulphamide can now be precipitated by adding silver nitrate and excess of ammonia, and on decomposing this compound with the necessary quantity of hydrochloric acid, a neutral or feebly acid soln. of sulphamide is obtained. Sulphamide is deposited in large, colourless crystals when its aq. soln. is evaporated over sulphuric acid under reduced press. 

F. Ephraim and M. Gurewitsch said that sulphamide of a high degree of purity is made by dissolving the product of the reaction between sulphuryl chloride and liquid ammonia in a small quantity of water and making the soln. just acid. After two or three days the hydrolysis is complete, the mixture is evaporated to dryness in a vacuum, and the residue extracted with ethyl acetate, which dissolves out the sulphamide, amidosulphonie acid and ammonium chloride being insoluble. After evaporating off the ethyl acetate, pure sulphamide, m.p. 93°, is left. 

W. Traube described the formation of what he called sulphimide, along with ammonia and imidosulphonic acid, when sulphamide is heated at 200°-210°. The solid product is treated with water, the soln. mixed with silver nitrate, and the precipitated silver sulphimide, purified by recrystallization, is decomposed with dil. hydrochloric acid. The aq. soln. decomposes when the attempt is made to isolate the solid, for when the soln. is evaporated below 40°, only ammonium hydrosulphate remains. A. Hantzsch and A. Holl found the soln. in ethyl acetate has properties in accord with the trimolecular formula sulphucyl trumide, or trisulphimide, (S02.NH)3—e.g. ebulliscopic determinations of the mol. wt. and the electrical conductivities of the aq. soln. of trisulphimide and its salts. They were able to isolate a crystalline solid by crystallization from ethyl alcohol which they considered to be trisulphimide itself. A. Hantzsch and B. C. Stuer, however, showed that the alleged compound is extremely unstable, and that the soln. obtained by W. Traube, and the solid obtained by A. Hantzsch and A. Holl, was really sulphuryl imidodiamide, only indications of the transient formation of trisulphimide in non-aqueous solvents were obtained. Trisulphimide acts as an acid, and a few salts have been reported. A. Hantzsch and B. C. Stuer consider that the compound has tautomeric forms—a true imide and an acid ... 

Carboxy and sulphamide groups may be annulated by treatment with a carboxylic organic acid. 

I Oral freshly prepared 3% aqueous chloramine T solution (syn. sodium sulphamide chloride or sodium tosylchloramide) is mixed with 40 ml 25% ethanolic trichloroacetic acid. 

Nickel sulfamate Nickel (II) sulfamate Nickel bis(sulphamidate) Nimate NSC 78888 Sulfamic acid, nickel(2+) salt (2 1). For nickel electroforming and plating aerospace and electronics application. Albright i Wilson Americas Inc. Atomergic Chemetals CK Witco Carp. ElfAtochem N. Am. M T Harshaw. 

The rearrangement of an Af-arylsulphonamide, or an JV-arylsulphamide, to the isomeric aminoaryl sulphonyl compound (equation 43) is now a well-known reaction. The reaction is the nitrogen analogue of the Fries rearrangement (Section III.A.). For sulphonamides, acid-catalysed, base-catalysed, thermally promoted and photochemically promoted rearrangements have been observed for sulphamides, only the thermal and base-catalysed processes have been reported. 

Sulphamoyl chloride when reacted with hydroperoxides in the presence of pyridine below — 30 °C leads to the formation of the novel alkyl sulphamoyl peroxides H2NS0200CH2R (R = CH2CH3, CH2CH2CH3) 303 (equation 98)305. Hydrolysis or ammonolysis of these compounds leads to formation of sulphamic acid or sulphamide respectively. 2-Nitrophenylsulphamoyl chloride (304), prepared from the corresponding sulphamic acid by reaction with PC15, has been used to prepare iV-(2-nitrophenyl)-iV -substituted sulphamides (305) and aryl esters (306) (equation 99)306. 

The synthesis, physical and chemical properties of sulphamides have been the subject of various reviews down through the years333-338. Sowada339 has summarized the three main synthetic routes in the preparation of sulphamides as follows (a) reaction of primary amines (alkyl or aryl) with sulphuryl chloride (b) reaction of primary amines with chlorosulphonic acid (c) reaction of primary amines (alkyl, cycloalkyl and aryl) with sulphamide. 

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