Hydroxylamines 0-sulphonic acid

The earliest use of a borohydride reagent for the enantioselective preparation of a chiral amine by amination of the corresponding alkene employed diisopinocampheylborane (50) prepared from (- -)-a-pmene . Thus c -2-butene [(Z)-51] was treated with 50 in diglyme to form an organoborane intermediate which, on treatment with hydroxylamine-0-sulphonic acid (52) in diglyme, gave (R)-2-aminobutane [(/f)-53], which after correction for the low enantiomeric excess of the (-l-)-a-pinene (68%) used to form 50, had an ee of 76%, but in rather low chemical yield (13%). ... 

The efficiencies of 0-(diphenylphosphinoyl)hydroxylamine and hydroxylamine-0-sulphonic acid as electrophilic aminating agents have been compared . The conversion of... 

Grignard reagents RMgX into the amines RNH2 succeeds with the former but fails with the latter. The two reagents gave comparable yields in the iV-amination of pyridine and quinoline but for indole and carbazole the first was more effective. It was concluded that, in general, hydroxylamine-O-sulphonic acid was more versatile. 1,2,3-Triazole reacts with hydroxylamine 0-sulphonic acid in aqueous potassium hydroxide to yield a mixture of 53% 1-amino-l,2,3-triazole and 14% of the 2-amino isomer (equation 37) . ... 

Organoboranes R2BH or R3B (R = C10H21, cyclohexyl or cyclooctyl etc.) react with hydroxylamine 0-sulphonic acid or its mesityl derivative or with chloramine to form primary amines... 

Direct amination of toluene can be effected with hydroxylamine-0-sulphonic acid, alkylhydroxylamines and hydroxylammonium salts in the presence of aluminium chloride (at least two moles per mole of aminating agent), and with hydrogen azide in the presence of aluminium chloride or sulphuric acid. These reactions lead to the corresponding toluidines. Thus toluene and hydroxylamine-0-sulphonic acid give mixed toluidines (50% yield) of the following composition ... 

Further examples of the Ritter reaction(cf. section IV.B) are provided by the many substituted olefins that may be protonated to ve carbonium ions which can be intercepted by hydrogen cyanide or organic nitriles cyanogen chloride can also be used as intercepting species , but offers no advantages. Mixtures of the two possible amides, and hence amines, are to be expected from non-terminal alkenes and from such olefinic compounds as oleic acid Olefins may also be converted to amines with yields of up to 60%, by hydroboration and subsequent reaction of the organoborane with chloroamine in alkaline solution or preferably with hydroxylamine-0-sulphonic acid in diglyme (reaction 86) The reaction is applicable... 

Gattefoss6 and Morel La Parfumerie Moderne, 1919, 114) describe a method for the production of vanillin by reducing nitrobenzene-sul-phonic acid with iron filings and hydrochloric acid in the presence of guaiacol and formic aldehyde. The first-named body is reduced to phenyl-hydroxylamine-sulphonic acid, which reacts with the guaiacol as follows —... 

Nitrohydroxylamine acid. Hydroxylamine sulphonic acid. Benzene sulphohydroximtc acid. 

Supplement 1952 2504-2665 Furfuracrylic acid, 300. Sulphonic acids, 667. Amines, 683. Hydroxylamines, 637. Hydrazines, 639. Azo compounds, 643. Diazo compounds, 661. Carbon-metal compounds, 663. 

The TV-amination of pyrazoles with hydroxylamine O-sulphonic acid in aqueous media at controlled pH allows the preparation of compounds with electron-withdrawing substituents85. 

Tlic foregoing sulphonic acids are all known, at least in the form of their salts, and are obtainable, directly or indirectly, by the interaction of sulphurous and nitrous acids or their salts. Isomerides of some of the sulphonic acids are also known, for example, hydroxylaminc-iso-sulphonic acid, NH. O.SOo.OH,1 which is obtainable by the action of chlorosulphonic acid on hydroxylamine hydrochloride. As its constitution indicates, this isomeric acid is in reality a derivative of permono-sulphuric acid (see p. 192). 

Hydroxylamine. Hydroxynitrilomono Hydroxynitrilodisulphonic Hydroxynltrilotrisulphonic sulphonic acid. acid. add. 

Add slowly and carefully hydroxylamine- (3-sulphonic acid (0.34 g, 3.0 mmol) to the reaction mixture. It is possible to observe that water is released from the mixture. 

Acetophenone and ring-substituted acetophenones condense with dimethylformamide diethyl acetal to give the enaminones 151, which yield 5-arylisoxazoles (152) by reaction with hydroxylamine O-sulphonic acid (equation 66)87. 

Sequential treatment of the enaminones 151 with phosphorus oxychloride and sodium sulphide yields the sulphur analogues 157, which yield isothiazoles by the action of hydroxylamine O-sulphonic acid (equation 69)87. 

The a-hydroxy-nitrone (72) is isomerised (toluene-p-sulphonic acid-benzene) to (81). Reduction of (81) with NaBH4 gives the hydroxylamine (83). Incomplete reduction leads to the nitrone (82). Oxidation of (83) with Cu gives the isomeric nitrone (84). The photochemistry of the nitrones (82) and (84) as well as that of the steroidal oxazirans has been studied. Nitrone (82) gives the two oxazirans (85) and (86), while (84) gives a mixture of the oxazirans (87). Irradiation of the oxazirans (87) leads to an azetidine (88, R = Ac). 

This ring is formed at room temperature when pyridine-2-acetic acid is stirred with hydroxylamine-<9-sulphonic acid. 

Diphenylphosphinylhydroxylamine offers some advantages over hydroxylamine-O-sulphonic acid as an aminating reagent,e.g. for N-heterocycles. 

Triaza-Compounds. 2-(Ethoxymethyleneamino)pyridine is converted into the triazolopyridine (564) by the action of hydroxylamine-O-sulphonic acid. Anodic oxidation of the hydrazone Ar NHN=CHAr (Ar =p-NO2C6H4, Ar = /7-MeC6H4) in the presence of pyridine and tetraethyl-ammonium perchlorate affords the salt (565). Oxidative cyclization of the pyridylhydrazone PyCH=NNHPy (Py = 2-pyridyl) by means of mercury(II) acetate yields compound (566). 2,4,6-Triphenylpyrylium fluoroborate reacts with amidrazones ArC(NH2)=NNH2 in the presence of triethylamine to give the pyrazolopyrimidines (567). The tricyclic compound (568) is... 

A test for sulphonic acids is based on conversion to the sulphonyl chloride and then reaction with hydroxylamine. The reaction product can be converted with a drop of acetaldehyde to a hydroxamic acid which is detected in the classical way through the brown-violet colour with a drop of a Fe3+ reagent264. 

An improved one-step conversion of alicyclic ketones (30) into lactams (31 n = 3-10) involves the use of hydroxylamine-O-sulphonic acid and methanoic acid at reflux temperature. Treatment of 1-chloro-l-nitroso- and 1-chloro-l-nitro-cycloalkanes (32) with PhaP and then hydrolysis of the intermediate chloro-imine provides a new route to (31 n — 3-6, or 10)." ... 

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