22607-10-9Relevant articles and documents
Biocatalytic synthesis of non-vicinal aliphatic diols
Ebrecht, Ana C.,Aschenbrenner, Jasmin C.,Smit, Martha S.,Opperman, Diederik J.
supporting information, p. 439 - 445 (2021/01/29)
Biocatalysts are receiving increased attention in the field of selective oxyfunctionalization of C-H bonds, with cytochrome P450 monooxygenases (CYP450s), and the related peroxygenases, leading the field. Here we report on the substrate promiscuity of CYP505A30, previously characterized as a fatty acid hydroxylase. In addition to its regioselective oxyfunctionalization of saturated fatty acids (ω-1-ω-3 hydroxylation), primary fatty alcohols are also accepted with similar regioselectivities. Moreover, alkanes such as n-octane and n-decane are also readily accepted, allowing for the production of non-vicinal diols through sequential oxygenation. This journal is
Thermal decomposition of diethylketone cyclic triperoxide in polar solvents
Barreto, Gaston P.,Alvarez, Elida E.,Eyler, Gladys N.,Canizo, Adriana I.,Allegretti, Patricia E.
, p. 881 - 886 (2014/07/07)
The thermolysis of diethylketone cyclic triperoxide (3,3,6,6,9,9-hexaethyl- 1,2,4,5,7,8-hexaoxacyclononane, DEKTP) was studied in different polar solvents (ethanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-2-propanol, and acetonitrile). The rate constant values (kd) are higher for reactions performed in secondary alcohols probably because of the possibility to form a cyclic adduct with the participation of the hydrogen atom bonded to the secondary carbon. The kinetic parameters were correlated with the physicochemical properties of the selected solvents. The products of the DEKTP thermal decomposition in different polar solvents support a radical-based decomposition mechanism. CSIRO 2014.
Olefin-dependent discrimination between two nonheme HO-Fev=O tautomeric species in catalytic H2O2 epoxidations
Company, Anna,Feng, Yan,Gueell, Mireia,Ribas, Xavi,Luis, Josep M.,Que Jr., Lawrence,Costas, Miquel
supporting information; experimental part, p. 3359 - 3362 (2009/12/06)
A study was conducted to demonstrate olefin-dependent discrimination of two nonheme HO-Fev=O tautomeric species in catalytic H2O 2 epoxidations. Mechanistic studies were carried out under the condition of excess of olefin to minimize over-oxidation reactions and all reactions for the study were carried out under a N2 atmosphere to prevent auto-oxidation process due to presence of O2. It was observed that the diol/epoxide (D/E) ration for these reaction was dependent on the specific olefin and ranged from 3/2 (cyclooctene) to 6/1 (1-octene). The oxidation of cyclooctene using H218O2 revealed that only 28% of the oxygen atoms in the epoxide derived from H 2O2. Mechanistic results suggested that HO-Fe v=O oxidant need to be labeled before its reaction with substrates.
Non-heme iron complexes for stereoselective oxidation: Tuning of the selectivity in dihydroxylation using different solvents
Klopstra, Marten,Roelfes, Gerard,Hage, Ronald,Kellogg, Richard M.,Feringa, Ben L.
, p. 846 - 856 (2007/10/03)
A new class of functional models for non-heme iron-based dioxygenases, including [(N3Py-Me)Fe(CH3CN)2](ClO4) 2 and [(N3Py-Bn)Fe(CH3CN)2](ClO 4)2 {N3Py-Me = [di(2-pyridyl)methyl]methyl(2-pyridyl) methylamine; N3Py-Bn = [di(2-pyridyl)methyl]benzyl(2-pyridyl)methylamine}, is presented here. NMR, UV and X-ray analyses revealed that six-coordinate low-spin FeII complexes with the pyridine N-atoms and the tertiary amine functionality of the ligand bound to Fe are formed. The two remaining coordination sites located cis to each other are occupied by labile CH 3CN groups that are easily exchanged by other ligands. We demonstrate that the reactivity and stereoselectivity of the complexes investigated depend on the choice of the solvent. The complexes have been examined as catalysts for the oxidation of both alkanes and olefins in CH3CN. In this solvent alkanes are oxidized to alcohols and ketones and olefins to the corresponding cis-epoxides and cis-diols. In acetone as solvent a different reactivity pattern was found, with, as the most striking example, the trans-dihydroxylation of cis-olefins. 18O-labeling studies in CH3CN establish incorporation of 18O from H218O2 and H218O in both the epoxide and the diol implicating an HO-FeV=18O active intermediate originating from an H 218O-FeIIIOOH species. These results are in full agreement with mechanistic schemes derived for other dioxygenase model systems. Based on labeling studies in acetone an additional oxidation mechanism is proposed for this solvent, in which the solvent acetone is involved. This is the first example of a catalyst that can give cis- or trans-dihydroxylation products, just by changing the solvent. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
Diastereoselective reduction of acyclic hydroxyketones and diketones with an indium hydride reagent
Yamada, Masafumi,Horie, Tomoaki,Kawai, Masao,Yamamura, Hatsuo,Araki, Shuki
, p. 15685 - 15690 (2007/10/03)
Hydroxyketones and diketones have been reduced with lithium indium hydride to give meso-diols selectively. α-Hydroxyketones and α-diketones are reduced to meso-1,2-diols with high diastereoselectivities, whereas the selectivities of β-hydroxyketones and β-diketones are less satisfactory.
The Synthesis of Glycols by Mercury-Photosensitized Alcohol Dehydrodimerization
Lee, Jesse C.,Boojamra, Constantine G.,Crabtree, Robert H.
, p. 3895 - 3900 (2007/10/02)
A variety of alcohols can be dehydrodimerized to give 1,2-diols on a multigram scale at 1 atm pressure and reflux temperature on photolysis (254 nm) in the presence of a trace of Hg vapor.Initial C-H bond breaking is followed by recombination of the resulting α-centered radicals, which normally leads to C-C bond formation α to oxygen.The reaction rate and selectivity can be increased by operating at lower temperatures under H2, in which case H atoms replace Hg* as the principal abstracting reagent and H atom abstraction from the α-CH bond leads directly to the α-C-centered radical.Under H atom conditions, unsaturated alcohols also react, in which case diols other than the 1,2-isomer can be formed selectively.The product can be rationalized on the basis of H atom addition to the C=C double bond to give the most stable radical which then dimerizes.For the special case of t-BuOH, H atom abstraction from the t-BuOH β-CH group under H atom conditions leads to the β-centered radical, which dimerizes to the 1,4-diol.Radical disproportionation accounts for some of the byproducts observed.The following previously unknown C-H bond strengths (kcal/mol) were determined from the results, assuming the literature BDE for the α-C-H of 2-propanol (91.0 +/-1.0); n-butanol, 92.8 +/- 1.0( α), 95.2 +/- 1.0 (β), and 94.3 +/- 1.0 (γ); n-propanol, 93.1 +/- 1.0 (α), and 95.0 +/- 1.0 (β), respectively.
Direct Catalytic Transformation of Olefins into α-Hydroxy Ketones with Hydrogen Peroxide Catalyzed by Peroxotungstophosphate
Sakata, Yasuyuki,Katayama, Yuji,Ishii, Yasutaka
, p. 671 - 674 (2007/10/02)
Aliphatic olefins were directly converted into α-hydroxy ketones with acidic aqueous hydrogen peroxide in the presence of catalytic amount of peroxytungstophosphate (PCWP) under the biphasic system using chloroform as a solvent.The acidic medium was necessary to open the resulting epoxide to vic-diol which was subsequently oxidized to α-hydroxy ketones.
PHOTOCHEMICAL REACTION OF ALCOHOLS - II. IRRADIATION OF AROMATIC ALCOHOLS
Balsells, R. Erra,Frasca, A. R.
, p. 2525 - 2538 (2007/10/02)
The UV irradiation of aromatic alcohols leads to the formation of several products: carbonyl compounds, ethers, α-glycols and tetra-aryl-1,4-dioxanes.The photoformation of α-glycols is qualitatively and quantitatively compared to the photoreduction of the carbonyl compounds.It is noteworthy that the glycols are formed with a stereochemistry very different depending upon whether the substrate is an alcohol or a carbonyl compound.The structure, configuration and conformation of the 1,4-dioxanes obtained are studied as well as their origin.Other aspects of the photochemistry of the alcohols are analyzed using hydroperoxides as model substrates.
PHOTOCHEMICAL REACTION OF ALCOHOLS-I IRRADIATION OF ALIPHATIC ALCOHOLS
Balsells, R. Erra,Frasca, A. R.
, p. 245 - 255 (2007/10/02)
The UV irradiation of aliphatic alcohols gave α-glycols as the principal products.The values of the dl-α-glycol to meso-α-glycol ratios obtained in each example were analyzed.The stereochemical course of the formation of α-glycols, their conformations and configurations were established on basis of 1H NMR data.
