10067-09-1Relevant articles and documents
Insights into gold-catalyzed synthesis of azelaic acid
Kulik, Anna,Martin, Andreas,Pohl, Marga-Martina,Fischer, Christine,Koeckritz, Angela
, p. 1799 - 1806 (2014)
A novel green route for the synthesis of azelaic and pelargonic acid via aerobic gold-catalyzed cleavage of 9,10-dihydroxystearic acid (DSA) was investigated recently. In this study, the examination of the reaction mechanism is described. The results of the application of 18O-labeled molecular oxygen and sodium hydroxide as well as of diastereomeric pure erythro- and threo-DSA were discussed. Assumed reaction intermediates were synthesized and subjected to the same reaction conditions as with DSA. As a conclusion from the obtained data, an oxidative dehydrogenation mechanism was postulated. Additionally, the aging of the gold catalyst used under different storage conditions was explored. the Partner Organisations 2014.
Catalytic Dihydroxylation of Olefins with Hydrogen Peroxide: An Organic-Solvent- and Metal-Free System
Usui, Yoko,Sato, Kazuhiko,Tanaka, Masato
, p. 5623 - 5625 (2003)
Green and convenient: Olefins are oxidized to 1,2-diols in high yield with 30% H2O2 in the presence of resin-supported sulfonic acid (see scheme) under metal-free conditions without any organic solvent. The catalyst can be recycled easily and is effective for at least 10 cycles.
Enantioconvergent transformation of racemic cis-dialkyl substituted epoxides to (R,R) threo diols by microsomal epoxide hydrolase catalysed hydrolysis
Bellucci, Giuseppe,Chiappe, Cinzia,Cordoni, Antonio,Ingrosso, Giovanni
, p. 9089 - 9092 (1996)
Both enantiomers of (±)-9,10-epoxystearic acid (1b), cis-(±)-5,6-epoxyhexadecane (1c) and cis-(±)-11,12-epoxyhexadecan-1-ol (1d) as well as the meso cis-9,10-epoxyoctadecane (1a) undergo microsomal epoxide hydrolase catalyzed hydration at the (S) carbon to give the corresponding (R,R) threo diols in a >90 e.e. Copyright (C) 1996 Elsevier Science Ltd.
Structural and solubility parameter correlations of gelation abilities for dihydroxylated derivatives of long-Chain, naturally occurring fatty acids
Zhang, Mohan,Selvakumar, Sermadurai,Zhang, Xinran,Sibi, Mukund P.,Weiss, Richard G.
, p. 8530 - 8543 (2015/06/02)
Creating structure-property correlations at different distance scales is one of the important challenges to the rational design of molecular gelators. Here, a series of dihydroxylated derivatives of long-chain fatty acids, derived from three naturally occurring molecules - oleic, erucic and ricinoleic acids - are investigated as gelators of a wide variety of liquids. Conclusions about what constitutes a more (or less!) efficient gelator are based upon analyses of a variety of thermal, structural, molecular modeling, and rheological results. Correlations between the manner of molecular packing in the neat solid or gel states of the gelators and Hansen solubility data from the liquids leads to the conclusion that diol stereochemistry, the number of carbon atoms separating the two hydroxyl groups, and the length of the alkanoic chains are the most important structural parameters controlling efficiency of gel formation for these gelators. Some of the diol gelators are as efficient or even more efficient than the well-known, excellent gelator, (R)-12-hydroxystearic acid; others are much worse. The ability to form extensive intermolecular H-bonding networks along the alkyl chains appears to play a key role in promoting fiber growth and, thus, gelation. In toto, the results demonstrate how the efficiency of gelation can be modulated by very small structural changes and also suggest how other structural modifications may be exploited to create efficient gelators.
Cork suberin molecular structure: Stereochemistry of the C18 epoxy and vic-diol ω-hydroxyacids and α,ω-diacids analyzed by nmr
Santos, Sara,Cabral, Vanessa,Graca, Jose
, p. 7038 - 7047 (2013/08/23)
Suberin is the biopolyester that protects the secondary tissues of plants against environmental variability and aggressions. Cork suberin is composed mostly of C18 ω-hydroxyacids and α,ω-diacids, 9,10-substituted with an unsaturation, an epoxide ring, or a vic-diol group. Although determinant for suberin macromolecular structure, the stereochemistry of these monomers is poorly studied, sometimes with contradictory results. An NMR technique was used here to assign the configuration of the 9,10-epoxy and 9,10-diol groups in C18 suberin acids, comparing the chemical shifts of diagnostic 1H and 13C signals with the ones of model compounds, before and after conversion of the vic-diol group into benzylidene acetal derivatives. The relative configuration was proved to be cis in the C18 9,10-epoxy and threo in the C18 9,10-diol suberin acids. These monomers were present in suberin probably as racemic mixtures, as shown by polarimetry. The revealed stereochemistry allows the suberin macromolecule to be built as an ordered array of midchain kinked C18 acids, reinforced by intramolecular hydrogen bonding.
Safe use of a toxic compound: Heterogeneous OsO4 catalysis in a nanobrush polymer microreactor
Basavaraju,Sharma, Siddharth,Maurya, Ram Awatar,Kim, Dong-Pyo
, p. 6735 - 6738 (2013/07/26)
Putting osmium in its place: The immobilization of hazardous OsO 4 on polymer nanobrushes in a microreactor is a safe, effective, and green concept. The method allows reactions to be performed in a time- and chemical-saving manner, with little environmental impact, as compared to spill-over bulk processes. Copyright
Prilezhaev dihydroxylation of olefins in a continuous flow process
Van Den Broek, Bas A. M. W.,Becker, René,K?ssl, Florian,Delville, Mari?lle M. E.,Nieuwland, Pieter J.,Koch, Kaspar,Rutjes, Floris P. J. T.
, p. 289 - 292 (2012/06/01)
Epoxidation of both terminal and non-terminal olefins with peroxy acids is a well-established and powerful tool in a wide variety of chemical processes. In an additional step, the epoxide can be readily converted into the corresponding trans-diol. Batch-wise scale-up, however, is often troublesome because of the thermal instability and explosive character of the peroxy acids involved. This article describes the design and semi-automated optimization of a continuous flow process and subsequent scale-up to preparative production volumes in an intrinsically safe manner. Olefins go with the flow: Prilezhaev dihydroxylation can be performed on a large scale in continuous flow microreactor systems in the oxidation of terminal and internal olefins. Major drivers for a continuous flow process include better control, improved safety, and a faster overall process, leading to a significantly higher throughput. Copyright
Electroorganic synthesis 65. Anodic homocoupling of carboxylic acids derived from fatty acids
Weiper-Idelmann, Andreas,Aus Dem Kahmen, Martin,Schaefer, Hans J.,Gockeln, Marianne
, p. 672 - 682 (2007/10/03)
Fatty acid derived carboxylic acids with double bonds, hydroxy-, amino-, keto-, ester- and epoxy groups are anodically coupled to dimers (Kolbe electrolysis) in 29 to 81% yield and up to a 2.5 mol scale. Problems due to the low conductivity of fatty acid salts were overcome by the use of a flow cell with a narrow electrode gap. Fatty acids with branched alkyl chains gave dimers with interesting emulsifying properties. Dimethyl hexadecanedioate, accessible from methyl azelate, could be cyclized and further converted into homomuscone and muscone in a few steps. A commercial mixture of dimeric fatty acids (C36-dicarboxylic acids) has been coupled to give C70-diesters. Acta Chemica Scandinavica 1998. Part 64: Nielsen, M. F., Batanero, B.,.
Kinetics and Mechanism of the Oxidation of Unsaturated Carboxylic Acids by Methyltributylammonium Permanganate in Methylene Chloride Solutions
Perez-Benito, Joaquin F.,Lee, Donald G.
, p. 3239 - 3243 (2007/10/02)
The product obtained when permanganate is reduced by unsaturated carboxylic acids under anhydrous conditions is manganese(III).The rate of reaction, which is subject to acid catalysis, exhibits a Hammet ρ value of 1.11 and inverse secondary isotope effects (kH/kD = 0.96-0.98) when the hydrogens on the double bond are replaced by deuterium.The involvement of a free-radical process is indicated by the formation of polymer during the oxidation of acrylic and methacrylic acids.The reaction is believed to be initiated by formation of an organometallic complex in which the double bond is a η2 ligand on manganese.Rearrangement of this complex results in the formation of a reactive manganate(V) cyclic diester, which undergoes a rapid (free-radical) reduction to manganese(III).
