1002-84-2Relevant articles and documents
Iron-catalyzed AlkylAlkyl negishi coupling of organoaluminum reagents
Agata, Ryosuke,Kawamura, Shintaro,Isozaki, Katsuhiro,Nakamura, Masaharu
, p. 238 - 241 (2019)
The first iron-catalyzed cross-coupling reaction of alkyl halides with alkylaluminum reagents (alkylalkyl Negishi coupling) is developed using an iron/bisphosphine catalyst system. The reaction shows high functional group tolerance: various primary alkyl halides possessing a non-protected indole, carboxyl, or hydroxy group are coupled with primary alkylaluminum reagents in good yields. Potassium fluoride plays a key role to promote the reaction by generating an aluminate species, which facilitates the transmetalation between the organoaluminum and the iron catalyst.
Determination of Key Hydrocarbon Autoxidation Products by Fluorescence
Shah, Ron,Pratt, Derek A.
, p. 6649 - 6656 (2016)
Hydroperoxides and carboxylic acids are key primary products that arise in the autoxidation of hydrocarbons. We have developed a simple approach to rapidly and simultaneously determine both types of products using hydroperoxide- and acid-sensitive moieties conjugated to nonpolar coumarin- and BODIPY-based fluorophores. The coumarin- and BODIPY-conjugated amine probes described here undergo 38- and 8-fold enhancement, respectively, upon protonation in a solvent system compatible with heavy hydrocarbons. The latter can be used directly with our previously described hydroperoxide-sensitive coumarin-conjugated phosphine probe to enable rapid quantification of both carboxylic acids and hydroperoxides in hydrocarbon samples. The utility of the approach is illustrated by the ready determination of the differing relative rates of hydroperoxide and acid formation with changes in hydrocarbon structure (e.g., n-hexadecane vs 1-hexadecene vs a lubricant base stock). The method offers significant versatility and automation compared with common but laborious titration approaches, and greatly improves screening efficiency and accuracy for the identification of novel radical-trapping antioxidants for high temperature applications. This application was demonstrated by the automated analysis of hydroperoxides and carboxylic acids (by microplate reader) in samples from 24 inhibited autoxidations of a lubricating oil, which were carried out on a parallel synthesizer at 160 °C in triplicate in a single day.
-
Karapetyan,Sh.A. et al.
, (1963)
-
Enantioselective α-hydroperoxylation of long-chain fatty acids with crude enzyme of marine green alga Ulva pertusa
Akakabe,Matsui,Kajiwara
, p. 1137 - 1140 (1999)
When palmitic acid was incubated with crude enzyme of marine green alga Ulva pertusa, (R)-2-hydroperoxyhexadecanoic acid was formed in high enantiomeric purity (>99%ee).
Kinetic study on the release of thiamine disulfide (TDS) from TDS-higher fatty acids complexes. II. Effect of odd-numbered fatty acids
Yokoyama,Ueda,Fujie
, p. 1819 - 1823 (1990)
-
-
Kuwata
, p. 560 (1938)
-
New 19α-hydroxyursane-type triterpenes from the leaves of Meyna spinosa (= Vangueria spinosa), Rubiaceae
Rudrapaul, Prasenjit,Das, Niranjan,De, Utpal Chandra,Dinda, Biswanath
, p. 7 - 10 (2014)
Two new 19α-hydroxyursane-type triterpenes, 2α,3α, 19α,24,28-pentahydroxyurs-12-ene (1) and meyanthic acid, 3β-acetoxy-2β,19α,23-trihydroxyurs-12-en-28-oic acid (2) along with one new aliphatic ester, myricyl pentadecanoate (3) and five known compounds, 1
-
Wynberg,Logothetis
, p. 1958,1960 (1956)
-
Synthesis of Carboxylic Acids by Palladium-Catalyzed Hydroxycarbonylation
Sang, Rui,Kucmierczyk, Peter,Dühren, Ricarda,Razzaq, Rauf,Dong, Kaiwu,Liu, Jie,Franke, Robert,Jackstell, Ralf,Beller, Matthias
supporting information, p. 14365 - 14373 (2019/09/06)
The synthesis of carboxylic acids is of fundamental importance in the chemical industry and the corresponding products find numerous applications for polymers, cosmetics, pharmaceuticals, agrochemicals, and other manufactured chemicals. Although hydroxycarbonylations of olefins have been known for more than 60 years, currently known catalyst systems for this transformation do not fulfill industrial requirements, for example, stability. Presented herein for the first time is an aqueous-phase protocol that allows conversion of various olefins, including sterically hindered and demanding tetra-, tri-, and 1,1-disubstituted systems, as well as terminal alkenes, into the corresponding carboxylic acids in excellent yields. The outstanding stability of the catalyst system (26 recycling runs in 32 days without measurable loss of activity), is showcased in the preparation of an industrially relevant fatty acid. Key-to-success is the use of a built-in-base ligand under acidic aqueous conditions. This catalytic system is expected to provide a basis for new cost-competitive processes for the industrial production of carboxylic acids.
