Aqueous solutions nitrone compounds

This compound is obtained by treating an aqueous solution of resorcin with nitrons acid (sodium nitrite and sulphuric acid). Dinitrosoresorcin crystallises from alcohol in yellowish-brown leaflets, which deflagrate at 115°. It is a pretty strong dibasic acid, and forms easily soluble salts with alkalies. 

Performance of the cyclization of compound 32 in methanolic solution in the presence of sodium methoxide, and in aqueous solution in the presence of potassium hydrogen carbonate (followed, in both cases, by cation exchange), gave similar results in regard to the isomeric-product composition.81 However, in the course of four days, an aqueous solution of a sodium nitronate mixture (33) underwent epimerization (see Section IV,2a p. 120), giving a different mixture... 

The full paper concerning the reaction of acyl chlorides (benzoyl and toluene-p-sulphonyl chlorides) with the steroidal nitrone derivative (23) of conanine has been published. Additional information concerning the mechanism of these reactions is given. Thus, it was shown that the formation of the a -benzyloxyimine (24) needs acidic conditions which favour the heterolysis of the N—O bond (Scheme 2). At room temperature, under Schotten-Baumann conditions, the epimeric compounds (25) were obtained from (23) with benzoyl chloride. Compound (25) gave (24) on refluxing in neutral solvent or by treatment with acid, whereas (24) was obtained directly from (23) when treated with a benzene solution of benzoyl chloride in the presence of aqueous sulphuric acid. 

This is the favored procedure for preparing 2,4,6-trinitrobenzaldehyde. Reaction (A) is run at room temperature in pyridine, using iodine as a catalyst, or in a alcohol-acetone mixture with anhydrous sodium carbonate as a catalyst. Reaction (B) proceeds in a strong aqueous hydrochloric acid solution overall yields are 39 to 52 percent. Reaction (A) can be run in an aqueous medium in the presence of light with a yield of 80 percent and less by-product formation than in the other methods. Other types of aromatic nitroso compounds, for example nitrosobenzene and nitrosotoluene, form nitrones according to the equation ... 

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