Emerson reaction

When oxidized by iron(III) ions 4-aminoantipyrine reacts with phenols to yield colored quinonoid derivatives (cf. 4-aminoantipyrine — potassium hexacyanoferrate(III) reagent in Volume 1 a). It is an oxidative coupling based on the Emerson reaction. 

Diene-Iron Carbonyl Complexes and Related Species R. Pettit and G. F. Emerson Reactions of Organotin Hydrides with Organic Compounds Henry C. Kuivila Organic Substituted Cyclosilanes... 

Aminoantipyrine-potassium ferricyanide for phenols (Emerson reaction). 

W. Emerson, Organic Reactions, Vol. IV, John WUey Sons, Inc., New York, 1948, Chapt. 3. 

Emerson, J.P., Farquhar, E.R. and Que, L. Jr. (2007) Structural snapshots along reaction pathways of non-heme iron enzymes. Angewandte Chemie, International Edition, 46, 8553-8556. 

The following calculations show the range of effects from infinitely slow hydration-dehydration to infinitely fast. Emerson (1975) and Kirk and Rachhpal-Singh (1992) and have made calculations allowing for the kinetics of the uncatalysed hydration-dehydration reactions, giving intermediate results. 

In 1884, Emerson-Reynolds reported deposition of PbS films by reaction between thiourea (thiocarbamide) and alkaline lead tartrate, where the metallic sulphide. .. became firmly attached as a specular layer to the sides of the vessel [6], A wide range of substrates, apart from that just mentioned (a glass beaker), was successfully used for this deposition porcelain, ebonite, iron, steel, and brass were specifically mentioned. Even more important, the deposits were very adherent, as quantified by their ability to withstand considerable friction with a wash-leather, and under this treatment take a fine polish. ... 

The physical constants of several other imines prepared by a similar procedure are shown in Table X. The aldimines listed in the Table can be obtained only if certain precautions are strictly observed [4b]. The method of Emerson, Hess, and Uhle [4c] could not be extended satisfactorily and the method described in Preparation 2-2 is a modification of the one described by Chancel [4d] for propylidenepropylamine. The reaction is best carried out by adding the aldehyde to the amine, without a solvent, at 0°C. When the order of addition is reversed, the yields are much lower. Potassium hydroxide is added at the end in order to remove the water formed during the reaction. The use of other drying agents such as potassium carbonate or magnesium sulfate failed to yield aldimines on distillation. The aldimines should always be distilled from fresh potassium hydroxide to yield water-white products. The aldimines are unstable and should be used within a few hours after their distillation otherwise polymeric products are obtained. 

The distinction between the antenna and the reaction centers grew out of experiments done by Robert Emerson... 

In trimethylenemethane complexes, the metal stabilizes an unusual and highly reactive ligand which cannot be obtained in free form. Trimethylenemethanetricar-bonyliron (R=H) was the first complex of this kind described in 1966 by Emerson and coworkers (Figure 1.2) [38]. It can be obtained by reaction of bromomethallyl alcohol with Fe(CO)5. Trimethylenemethaneiron complexes have been applied for [3+2]-cycloaddition reactions with alkenes [39]. 

A major benthic process, that had only casually been considered for its potential influence on carbonate accumulation in deep sea sediments, is the oxidation of organic matter. The general reaction for this process involving marine organic matter is (Emerson and Bender, 1981) ... 

In his rejection of the Emerson model, Rabinowitch went on to say The difficulty of the phosphate storage theory appears most clearly when one considers the fact that, in weak light, eight or ten quanta of light are sufficient to reduce one molecule of carbon dioxide. If each quantum should produce one molecule of high-energy phosphate, the accumulated energy would be only 80-100 kcal per Einstein—while photosynthesis requires at least 112 kcal per mole, and probably more, because of losses in irreversible partial reactions (Vol. 1, p. 228). 

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