2283-08-1Relevant articles and documents
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Hunsberger
, p. 5626,5630 (1950)
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Carboxylations of alkali metal phenoxides with carbon dioxide
Kosugi, Yoshio,Imaoka, Yoshio,Gotoh, Fumisato,Rahim,Matsui, Yoshihisa,Sakanishi, Kinya
, p. 817 - 821 (2003)
The reaction mechanism of the Kolbe-Schmitt reaction of phenol and 2-naphthol has been investigated. An alkali metal phenoxide-CO2 complex is not an intermediate that can be easily transformed into a carboxylic acid, such as salicylic acid (SA) and p-hydroxybenzoic acid (pHBA). A direct carboxylation of phenoxide with CO2 takes place even at room temperature, and is competitive with the formation of the CO2 complex. The resulting complex decomposes thermally (above ca. 100°C) to phenoxide, which then undergoes further competitive reactions. Experiments using a carbon-13 labeled complex support a mechanism of direct carboxylation, and not the mechanism via a CO2 complex. The reactivity, C-13 NMR and MOPAC/PM3 calculations suggest a new carbonate-like structure for the CO2 complex.
An Efficient Carboxylation of 1-Naphthols using Magnesium Methyl Carbonate
Cate, Laurence A.
, p. 385 - 386 (1983)
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Catalyst-free aerobic oxidation of aldehydes into acids in water under mild conditions
Zhang, Yue,Cheng, Yujia,Cai, Huizhuo,He, Shaopo,Shan, Qiheng,Zhao, Hongwei,Chen, Yiping,Wang, Bo
supporting information, p. 5708 - 5713 (2017/12/06)
The first example of catalyst-free aerobic oxidation of aldehydes in water under respective acidic, neutral and alkaline conditions was developed. The sole oxidant is molecular oxygen of 1 atmosphere and reactions can proceed under extremely mild conditions. This procedure covers a wide range of aldehydes, and operates easily. No additives and catalysts were required for this purpose, and most of the aldehydes can be converted to their corresponding carboxylic acids with good to excellent yields, in addition, no side-product formation could be observed during or after the reactions. To well illustrate why the oxidation rate becomes fast firstly and then slows with increased temperatures, five control reactions were carried out and a Fe3+/Fe2+ recycling system was introduced to facilitate the aldehyde oxidation rate. The generality of this method offers the potential for industrial aldehyde-containing waste water treatment.
Oxidation of 2-hydroxynaphthaldehyde by alkaline N-bromosuccinimide - A kinetic and mechanistic study
Naik, Govindrajnaj T.,Angadi, Mahantesh A.,Harihar, Abdulazizkhan L.
experimental part, p. 255 - 260 (2010/04/05)
The kinetics of the oxidation of 2-hydroxynaphthaldehyde (2-HNA) by N-bromosuccinimide (NBS) in aqueous alkaline medium at a constant ionic strength of 0.60 mol dm-3 was studied titrimetrically. The reaction is of first order in [NBS] and of fractional order in both [2-HNA] and [alkali]. Addition of products has no significant effect on the reaction rate. However, increasing ionic strength and decreasing dielectric constant of the medium increases the rate. The oxidation process in alkaline medium has been shown to proceed via the formation of a complex between the active species of the oxidant and the substrate followed by the decomposition of the complex in a slow rate determining step to yield the product. Some reaction constants involved in the mechanism were determined. The calculated and observed rate constants agree excellently. The activation parameters were computed with respect to the slow step of the mechanism.