149-57-5Relevant articles and documents
Preparative microdroplet synthesis of carboxylic acids from aerobic oxidation of aldehydes
Yan, Xin,Lai, Yin-Hung,Zare, Richard N.
, p. 5207 - 5211 (2018)
Single liquid-phase and liquid-liquid phase reactions in microdroplets have shown much faster kinetics than that in the bulk phase. This work extends the scope of microdroplet reactions to gas-liquid reactions and achieves preparative synthesis. We report highly efficient aerobic oxidation of aldehydes to carboxylic acids in microdroplets. Molecular oxygen plays two roles: (1) as the sheath gas to shear the aldehyde solution into microdroplets, and (2) as the sole oxidant. The dramatic increase of the surface-area-to-volume ratio of microdroplets compared to bulk solution, and the efficient mixing of gas and liquid phases using spray nozzles allow effective mass transfer between aldehydes and molecular oxygen. The addition of catalytic nickel(ii) acetate is shown to accelerate further microdroplet reactions of this kind. We show that aliphatic, aromatic, and heterocyclic aldehydes can be oxidized to the corresponding carboxylic acids in a mixture of water and ethanol using the nickel(ii) acetate catalyst, in moderate to excellent yields (62-91%). The microdroplet synthesis is scaled up to make it preparative. For example, aerobic oxidation of 4-tert-butylbenzaldehyde to 4-tert-butylbenzoic acid was achieved at a rate of 10.5 mg min-1 with an isolated product yield of 66%.
The Regiospecific Palladium Catalysed Hydrocarboxylation of Alkenes under Mild Conditions
Alper, Howard,Woell, James B.,Despeyroux, Bertrand,Smith, David J. H.
, p. 1270 - 1271 (1983)
Alkenes react with carbon monoxide, water, oxygen, hydrochloric acid, and palladium and copper chlorides, to give branched chain acids in good yields.
Physicochemical properties of 2-ethylhexanoic acid N′,N′- dialkylhydrazides
Radushev,Batueva,Gusev
, p. 1196 - 1200 (2006)
The following characteristics of 2-ethylhexanoic acid N′,N′- dialkyl(C4-C8)hydrazides relevant to their potential application as Cu(II) extractants were studied: solubility, acid-base properties, resistance to hydrolysis, loss with the aqueous phase, and distribution ratio in relation to the composition of the medium and length of alkyl chains. Nauka/Interperiodica 2006.
Mechanistic Insights into the Aerobic Oxidation of Aldehydes: Evidence of Multiple Reaction Pathways during the Liquid Phase Oxidation of 2-Ethylhexanal
Vanoye, Laurent,Favre-Réguillon, Alain
, p. 335 - 346 (2022/02/10)
The liquid-phase aldehyde oxidation by molecular oxygen (autoxidation) has been known for about 2 centuries and is a critical organic transformation in both industrial applications and academic research. However, the general reaction pathway proposed for the aerobic oxidation of aldehydes into the corresponding carboxylic acid exhibits some inconstancies, in particular, for β-substituted aliphatic aldehydes. Thus, the liquid-phase aerobic oxidation of 2-ethylhexanal was further studied in acetonitrile at 20 °C with O2 at atmospheric pressure. By precisely monitoring the primary intermediate (peracid), product (carboxylic acid), and byproducts as a function of time and catalysts used, we demonstrated the pivotal role of the acylperoxy radical. The direct formation of peracid and carboxylic acid from the latter was highlighted by analyzing the composition of the reaction mixture at low conversion. Peracid could be converted into carboxylic acid by metal catalysts or through reaction workup. Consequently, the commonly accepted pathway of aerobic oxidation of aldehyde via a Criegee intermediate can be overlooked under these conditions.
Preparation method of bimetallic catalyst oxidation aldehyde synthetic carboxylic acid (by machine translation)
-
Paragraph 0050-0051, (2020/05/30)
The method is, in a reaction solvent: under normal pressure oxygen condition, under the action of a bimetallic catalyst under the action of a bimetallic catalyst under the action of a bimetallic catalyst under the action of a bimetallic catalyst, at, DEG, under stirring . under a stirring condition with an aldehyde compound as a substrate 10-90 °C in a reaction solvent under, a stirring condition under the action of a bimetallic catalyst . The reaction solution is stirred, for. 1-12h, hours at; room temperature, under, the action, of a bimetallic 1:1 catalyst Cu(OAc) under the action of a bimetallic catalyst under the action of a bimetallic catalyst under the action of a double-metal catalyst. 2 · H2 O And Co(OAc)2 · 44H2 O As the bimetallic catalyst, can achieve the highest yield of the carboxylic acid product, in high yield, by adjusting the reaction temperature, solvent, catalyst amount, for different types of the raw material aldehyde 98%. (by machine translation)
PROCESSES FOR PRODUCING CARBOXYLIC ACIDS
-
Page/Page column 0043, (2020/10/20)
Processes are disclosed for preparing carboxylic acids from organic esters, the processes comprising contacting an ester with water in the presence of an acid catalyst and a homogenizing solvent at conditions effective to form a carboxylic acid. The homogenizing solvent is present in an amount sufficient to form a single-phase reaction mixture comprising the ester, water, and homogenizing solvent. The homogenizing solvent may be selected from acetonitrile, dimethyl sulfoxide, and 1,4-dioxane.
