O-Methylhydroxylamine

The condensation products of 39 with hydroxylamine, O-methylhydroxylamine, malononitrile or dimethyl malonate have been formulated as 41 and 42.235... 

A similar but less useful amination reaction was reported by the Erdik group.426,427 They found that diarylzincs and trialrylzincates reacted with acetone 0-(2,4,6-trimethylphenylsulfonyl)oxime 327 and O-methylhydroxylamine in the presence of GuGN. The products of this reaction were hydrolyzed to afford the corresponding primary amines in modest yield (Scheme 167). 

In carbonyl addition reactions, a commonly occurring and important mechanistic step is the transfer of a proton from one site to another in a reactive intermediate (proton switch). If the proton switch occurs sufficiently rapidly compared with the rate of collapse of the intermediate to reactants, the overall reaction may be facilitated by trapping of the unstable intermediate by the proton switch (Jencks, 1976). For example, in the formation of oximes from the reaction of benzaldehyde with O-methylhydroxylamine shown in (87H89) (Sayer and Jencks, 1973 Rosenberg et al., 1974), the first unstable intermediate (It) on the reaction pathway is converted by a proton switch (88) to the intermediate (I2) which has less tendency than It to... 

Recently a quantitative method for the determination of carbonyl groups in oxidized xylan has been developed.106 The method involves the reaction of the carbonyl group with O-methylhydroxylamine hydrochloride to form the corresponding oxime with the liberation of one mole of titratable acid. 

Intermolecular coupling between ketones and 0-methyl oximes, hydrazones and nitrones is achieved on reduction at a tin cathode in isopropanol [105]. It is not clear which of the reacting species accepts the initial electron in these processes. The reaction with 0-methyloximes, followed by catalytic reduction of the first formed O-methylhydroxylamine, is a convenient synthetic route to 2-amino-alcohols. 

Several methods have been reported for the synthesis of 0-aLkylhydroxylamines . O-Methylhydroxylamine la can be prepared by a one-step procedure or can be obtained from its commercially available hydrochloride salt . Methods for the preparation of O-(nitrophenyl) hydroxylamines have been reviewed. They are stable and commercially available. 

Recently, a direct kinetic study on the amination of substituted phenyhnagnesium bromides using Af,Af-dimethyl O-mesitylenesulfonyl hydroxylamine 3b as amination reagent has been reported by Erdik and Ate Ulkii . Rate data, the Hammett relationship and activation entropy support an Sn2 displacement of the carbon nucleophile on the electrophilic nitrogen. These results are consistent with the competition kinetics for electrophilic amination of substituted phenyl Grignard reagents with O-methylhydroxylamine In. ... 

NOCH3. HC1 by heating the di-K salt of o-methylhydroxylamine-N,N-disulfonic acid in dilute acid soln. Explodes at 300°. Atomic constants and IR spectra have been measured (Ref 1)... 

Aminoferrocene (XXXV) can be prepared in low yield by treatment of O-methylhydroxylamine or O-benzylhydroxylamine with ferrocenyllithium (1, 65). Nitroferrocene (XXXVI), unattainable by direct nitration of ferrocene, can be isolated from the reaction of ferrocenyllithium and either n-propyl nitrate or dinitrogen tetroxide at —70° (30, 36). A similar reaction between ferrocenyllithium and nitrous oxide leads to azoferrocene (XXXVII) (08). 

Lithiation of dibenzofuran with butyllithium and mercuration both occur at the 4-position. Thallation occurs at the 2-position, however (57IZV1391). The mercury and thallium derivatives serve as a source of the iodo compounds by reaction with iodine. Bromodibenzofurans undergo bromine/lithium exchange with butyllithium and the derived lithio compounds may be converted into phenols by reaction with molecular oxygen in the presence of a Grignard reagent, into amines by reaction with O-methylhydroxylamine, into sulfinic acids by reaction with sulfur dioxide, into carboxylic acids by reaction with carbon dioxide and into methyl derivatives by reaction with methyl sulfate (Scheme 100). This last reaction... 

Cyclization of N-alkyloxygly collie acid amides. These amides, e.g. 172 are readily obtainable from O-methylhydroxylamine and the appropriate acid with dicyclohexylcarbodiimide, and on refluxing in carbon tetrachloride with the same reagent, cyclization occurs to 173 [85ZN(B)398]. A similar cyclization is effected by thionyl chloride in the presence of l,l -thionyldiimidazole (86AP1084). 

The first scientific articles from the IKhPS were submitted for publication in the early 1960s, among them being Nikolay s reports on his work in the new field. His major project in nucleotide chemistry was specific chemical modifications of heterocyclic bases. Reactions of hydroxylamine with cytidine and uridine were studied in detail and a new reagent, O-methylhydroxylamine, was proposed for modification of cytidine. These investigations aimed at the development of efficient methods for sequencing and analysis of the secondary structure of polynucleotides. Later, a reaction of chloroacetaldehyde with adenosine and cytidine was discovered and used for preparation of fluorescent polynucleotide derivatives. 

Substituent effects on the rate of electrophilic amination of phenylmagnesium bromides, magnesium diphenylcuprates, and catalytic phenylzinc cyanocuprates with O-methylhydroxylamine in THF have been investigated in a competitive kinetic study.169 The mechanistic differences between these three reactions were discussed on the basis of the experimental results. 

The final polycyclic aromatic hydrocarbon that was investigated <2000EJ0335> is benzo[fixed double bond like phenanthrene. Its cross-ozonolysis with formaldehyde gave none of the normal ozonide 120, but mainly the aldehydic ozonide 117. At room temperature, a substantial amount of opening of the ozonide ring occurred with the formation of the acid aldehyde 121. Both products 117 and 121 could be stabilized by treatment with O-methylhydroxylamine, yielding products 118 and 122, respectively. The separate co-ozonolysis of compound 117 with vinyl acetate afforded the diozonide 119 (Scheme 37 and Table 16). The cross-ozonolysis with acetyl cyanide followed by treatment of the crude reaction mixture with O-methylhydroxylamine yielded the O-methyloxime of the cross-product. Cross-ozonolysis with benzoyl cyanide was not successful, and only the normal mono-ozonide 120 was formed. 

The participation of ammonia [that can apparently be replaced by O-methylhydroxylamine (30)] may be related to a second function of the enzyme, accomplished in the case of the activation of HCOs", and only in that case (Reaction 13) ... 

O-Methylhydroxylamine hydrochloride (0.4mol) and lOg 3A molecular sieves were added to a solution of the product from Step 1 (0.1 mol) dissolved in 50 ml methyl alcohol and the mixture stood at ambient temperature 16 hours. The solution was concentrated, the residue partitioned between methyl t-butyl ether and water, the organic phase washed, dried, concentrated and the product isolated in 100% yield as 1 1 E/Z isomer mixture. H-NMR data supplied. (Note 3)... 

A general method for the preparation of primary amines, free from secondary and tertiary amines, involves the interaction of Grignard reagents and O-methylhydroxylamine. The yields range from 45% to 90% for many amines including ethylamine (81%), t-butylamine (70%), n-amyl-amine (65%), and /3-phenylethylamine (68%)/ ... 

Grignard reagents which have been prepared from polymethylene halides and magnesium in the presence of 0.1% water in the ether react readily with O-methylhydroxylamine to form the corresponding polymethylene diamines (50-68%). ... 

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