Sulphamate ion

Candlin JP, Wilkins RG. Sulphur-nitrogen compounds. Part I. The hydrolysis of sulphamate ion in perchloric acid. J Chem Soc 1960 4236-4241. 

The structure of the aminosulphonate (sulphamate) ion, SO3NH2, has been accurately determined in the K salt, (i). Since the angles S—N-H and H—N—H are both 110° the N bonds are not coplanar, as suggested by an earlier X-ray study. We may include here two zwitterions. A n.d. study of sulphamic acid, 038. NH3, shows that the molecule has approximately the staggered configuration, (n). Of special interest are the N-H—O bonds (2-93-2-98 A) in which the N—H bond... 

The absorption of sulphamate ions (26) on Hg electrodes was studied by measuring the double layer capacitance in solutions of ammonium sulphamate maintained at constant ionic strength with ammonium fluoride54... 

A kinetic analytical procedure for the estimation of trace levels of sulphamate ion has been reported by Wei156. The procedure is based on the ability of the sulphamate ion to inhibit the oxidation of ferrous ion by nitric acid. A linear relationship between the log of the inhibition time and concentration of the sulphamate ion over the range 6 x 10 3 to 4 x 10"1 g 1 1 with deviations less than 0.03 mg was assessed. No interference by S042-, Ni2 +, Co2+, Cu2+ and Mn2+ ions on the estimation of the sulphamate was reported. 

A number of studies have been reported on the reduction of nitrate by metal ions. In dilute HNO3 solution, the ruthenium(ii) species [(py)(bipy)2Ru(OH2)]2+ is oxidized by NO3- to the corresponding Ru complex. The metal nitrosyl cation [(py)(bipy)2Ru(NO)] + is also formed as a product, resulting from the nitrosation reaction of (initial product) HNO2 with ruthenium(ii) aquo-species. This side reaction is eliminated when the HNOj scavenger sulphamate ion (N112803") is present. The reaction mechanism involves an initial substitution of the nitrate to yield the species [(py)(bipy)2Ru(0 -NOa)], which in an intramolecular redox step produces HNOa and a ruthenium(iv) ion,... 

Sulphates. Sulphate ion may be generated by the hydrolysis of aminosulphonic (sulphamic) acid ... 

The barium sulphate may be precipitated either by the use of sulphuric acid, or from homogeneous solution by the use of sulphamic acid solution which produces sulphate ions on boiling ... 

Patterson function will show maxima on this plane at positions which give immediately the actual coordinates of these atoms. Similar considerations were used in the determination of the structure of potassium sulphamate NH2SO3K (Brown and Cox, 1940) it was known that the y coordinates of the potassium ions are 0 and while those of the sulphur atoms are and consequently, the Patterson function on the plane y = l shows maxima at positions corresponding to K-S vectors. Atomic positions are not given directly, but can be derived from the positions of Patterson peaks by a consideration of the equivalent positions in the space-group. 

Sulphite ion reacts with sulphamate , the rate equation, corrected for the back reaction, being (c/, also p. 305)... 

In NaHPOa(NH2) there are zwitterions H3N.PO3 , (d), analogous to the isoelectronic sulphamic acid, (e), H3N. SOJ (p. 586). The N-H-0 bonds link the ions into a 3-dimensional framework, in the interstices of which are located the Na ions. Replacement of one 0 by S in PO3NH2" gives the ion [P02S(NH2)] in which the bond lengths shown at (f) come from a study of the di-ammonium salt. There are similar bond lengths in the diamidothiophosphate ion, studied in NH4 [P0S(NH2)2]. ... 

The kinetics of the electrochemical reduction of sulphamic acid giving sulphite ion and ammonium hydroxide have been studied polarographically in aqueous solution in the presence of various salts51. The electrodissolution of lead sulphide, prepared by fusion or by sintering in sulphamic acid, has been measured by cyclic voltammetric, potentiodynamic and potentiostatic methods52. 

Intermolecular acid catalysis using a series of mainly carboxylic acids involves reaction of N-protonated naphthyl sulphamate with carboxylate anions in the rate-determining step. The / nuc value for attack (0.33) is similar to that reported by the same group for the reaction of phenolate ions with tertiary amine sulphonate (0.23). Stereoelectronic effects are suggested as governing the type of mechanism operating in these systems. 

The phase transfer catalysis process has also been extended to synthesize the alkyl and aryl esters (170) of N-aryl sulphamic acids212 (equation 23). If the ratio of aliphatic alcohol (169) to sulphamoyl chloride (168) is increased from 1 1 to 2 1, then N-alkyl-iV-arylsulphamate esters (171) with similar alkyl groups are obtained together with considerable amounts of iV-arylsulphamic acid esters (170). The exclusive formation of the iV-alkyl-iV-arylsulphamate esters (171) can be achieved by employing longer reaction times. A second approach to the synthesis of 171 would be to react the iV-methyl-iV-phenyl sulphamoyl chloride (172) with the alcohol. This was attempted, but the ester failed to form even under forcing conditions. The corresponding AT-alkyl iV-arylsulphamate ion (173) was isolated (equation 24) hydrolysis to the acid was considered to occur as opposed to nucleophilic displacement of the chloride by the methanol. 

Because of tropolonium ion formation, tropolone remains unaffected by fuming sulphuric acid at 100 - 150° [302]. It may however be sulphonated by being heated with sulphamic acid [302]. In the case... 

Fig. 46. The dependence of the distribution coefficients of several ions on zirconium phosphate on the aqueous HNO3 concentration. All adsorbates present in tracer amounts. Solutions of Pu(in) were 0.005 in sulphamic acid and 0.015 in Iwdrazine solutions of Pu(IV) 0.02 M in NaNOg and solutions of Pu02 0.02 M in KBrOs. ... 

Sulphamic acid solution liberates sulphate ions slowly on boiling. When mixed with the barium solution, barium sulphate precipitates slowly giving a more easily filtrable precipitate. NH2S0jH+H20-+NH4++S04 -+H+... 

Tracer studies have shown that the isomerization of /ra/zj-[Co(en)2(NH3)-(SCN)] to the A-thiocyanato-linkage isomer in basic aqueous solution is intramolecular. The detailed mechanism may involve an intimate ion pair which does not exchange its thiocyanate with the thiocyanate in solution, a species in which the thiocyanate is Ji-bonded to the cobalt, or intramolecular attack of a deprotonated amine nitrogen at the thiocyanate carbon (Scheme 5). Aquation of [Co(NH3)5(sulphamate)] - is preceded by isomerization of the starting complex to an equilibrium mixture of N- and 0-bonded isomers. The specific rate constant for approach to equilibrium is l.lxlO s at 25 °C composite activation parameters are AH = 24.7 kcal mol and AS = 10.9 cal deg mol . Inability to estimate the equilibrium constant satisfactorily precludes the separation of these kinetic parameters into their forward and backward components. ... 

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