Teuber reaction

Tetryl Tetrytols Teuber reaction Teutsch route Tevdek II... 

The nitrosodisulfonate salts, particularly the dipotassium salt called Fremy s salt, are useful reagents for the selective oxidation of phenols and aromatic amines to quinones (the Teuber reaction). - Dipotassium nitrosodisulfonate has been prepared by the oxidation of a hydroxylaminedisulfonate salt with potassium permanganate, " with lead dioxide, or by electrolysis. This salt is also available commercially. The present procedure illustrates the electrolytic oxidation to form an alkaline aqueous solution of the relatively soluble disodium nitrosodisulfonate. This procedure avoids a preliminary filtration which is required to remove manganese dioxide formed when potassium permanganate is used as the oxidant. " ... 

The classical and the most useful laboratory method for the preparation of quinones is the oxidation of monohydric phenols with the radical reagent, potassium nitrosodisulphonate [(K03S)2NO] (Fremy s salt) (the Teuber reaction).5 Details for the conversion of 3,4-dimethylphenol into 3,4-dimethyl-1,2-benzoquinone may be regarded as typical55 the probable mechanistic pathway is formulated below. 

The oxidation of phenols with Fremy s radical, dipotassium nitrosodisulfonic acid [N0(S03K)2, 7.34], to hydroquinones is known as the Teuber reaction . The disodium salt of nitrosodisulfonic acid [N0(S03Na)2] is also used for the oxidation of phenols. 

Primin (2-methoxy-6-n-pentyl-1,4-benzoquinone) has been synthesised from the oxidation of 2-methoxy-6-n-pentylphenol with Fremy s salt (the Teuber reaction) by the route indicated (ref. 46). 

Teuber reaction 8, 206 16, 222 Thallium(III) acetate 19, 189 —, oxidations with — 18,185 Thallium(I) hydroxide 16, 334 Theophyllines... 

Teuber, S.S. and W. R. Peterson. Systemic allergic reaction to coconut (Cocos nucifera) in 2 subjects with hypersensitivity to tree nut and demonstration of cross-reactivity to legu-min-like seed storage proteins new coconut and walnut food allergens. J Allergy Clin Immunol 1999 103(6) 1180-1185. 

Because of their relatively high reactivity, the foregoing structures often appear as transient intermediates in a series of reactions rather than as end products. Several of the documented reactions of these intermediates include rearomatization (e.g., reduction to catechol and hydroquinone derivatives), further oxidation to mono- and dicarboxylic acids (see below), benzylic acid rearrangements (Corbett 1966, Corbett and Fooks 1967), cycloaddition reactions (Teuber et al. 1966), and various condensation reactions (Erdtman and Granath 1954). The last-named processes, which are accelerated in acidic and basic media, often give rise to structurally complex and poorly defined materials. 

Quintanilla-Licea R, Teuber HJ (2001) Review on reactions of acetylacetaldehyde with aromatic and biogenic amines and indoles-synthesis of heterocycles via hydroxymethylene ketones. Heterocycles 55 1365-1397... 

Teuber SS, Reilly DA, Howell L, Oide C, Gershwin ME. Severe migratory granulomatous reactions to silicone gel in 3 patients. J Rheumatol 1999 26(3) 699-704. 

The most common solvents are aqueous alcohol and aqueous acetone and the reaction is usually buffered with phosphate or acetate. The reaction is rapid and may be monitored by disappearance of the purple color of the radical. A simple mechanism for the oxidation was proposed by Teuber and Rau.203 Electron transfer from Fremy s salt to phenol generates a radical species (126), and this reacts with excess Fremy s salt to give an addition product, 127. Loss of the hydrogen a to the oxygen moiety in 127 leads to formation of the quinone (124) and potassium aminodisulfonate [ HN(S03K)2 ]. 

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