533-60-8Relevant articles and documents
Selective oxidation of 1,2-diols by electrochemical method using organotin compound and bromide ion as mediators
Maki, Toshihide,Fukae, Kazuhiro,Harasawa, Hitomi,Ohishi, Takahiro,Matsumura, Yoshihiro,Onomura, Osamu
, p. 651 - 654 (1998)
A new electrochemical method for a selective oxidation of 1,2-diols to keto alcohols was explored. The method used dibutyltin oxide and bromide ion as mediators, and the oxidation was found to proceed effectively at 0°C under neutral conditions. Under these reaction conditions, 1,2-cyclohexanediol was selectively oxidized even in the presence of primary and secondary alcohols.
A zinc-dependent alcohol dehydrogenase (ADH) from Thauera aromatica, reducing cyclic α- And β-diketones
Loderer, Christoph,Morgenstern, Frances,Ansorge-Schumacher, Marion
, p. 1872 - 1880 (2015)
Zinc-dependent alcohol dehydrogenases (ADHs) are valuable biocatalysts for the synthesis of chiral hydroxy compounds such as α-hydroxy ketones and diols, both valuable precursors for the synthesis of various pharmaceuticals. However, while highly active on aliphatic or phenyl-substituted diketones, most well characterized ADHs show no significant activity on cyclic α- and β-diketones. Therefore, this study aimed at the detection of a novel ADH capable to reduce these special targets. It involved a rational screening of biochemical pathways for enzymes with structurally related natural substrates. The so detected 6-hydroxycyclohex-1-ene-1-carbonyl-CoA dehydrogenase (ThaADH) from Thauera aromatica was cloned, expressed in Escherichia coli and purified by affinity chromatography. The characterization revealed a substrate specificity with highest activities on cyclic α- and β-diketones including 1,2-cyclohexanedione and 1,3-cyclopentanedione. Structural reasons for this extraordinary substrate spectrum were investigated with a homology model created via Swiss Model server. Although the quality of the model may be improved, it suggests that a bulky aromatic residue, that plays a crucial role in the definition of the substrate binding pockets of most ADHs, is replaced by a glycine residue in ThaADH. We propose that this structural difference leads to the formation of one large binding pocket instead of two smaller ones and consequently to a preference for cyclic diketones over linear bulky substrates. Thus, we have achieved both provision of a novel biocatalyst with high potential in chiral synthesis, and a possible explanation for the measured differences to known ADHs. The described structural motif might be used for identification of further enzymes with a related substrate scope.
Citric acid mediated catalytic osmylation/oxidative cleavage of electron deficient olefins: A vinyl sulfone study
Bobinski, Thomas P.,Fuchs, Philip L.
, p. 4151 - 4154 (2015)
The first broad catalytic dihydroxylation of enantiopure cyclic vinyl sulfones followed by oxidative cleavage of the resulting acyloin provides linear termini-differentiated polyketide fragments. This mild vinyl sulfone cleavage provides an effective alternative to the current ozonolysis protocol.
Aerobic photooxidation in water by polyoxotungstates: The case of uracil
Bonchio, Marcella,Carraro, Mauro,Conte, Valeria,Scorrano, Gianfranco
, p. 4897 - 4903 (2005)
Uracil photooxygenation occurs in acidic water (pH = 1) at 25°C, under oxygen (1 atm), irradiating with γ > 300 nm in the presence of selected polyoxometalates (POM). A marked diversity of photocatalytic behavior is registered for different POMs in terms of oxidation rate and selectivity. H 3PW12O40 (PW12) appears to be the most reactive photocatalyst, by far superior to isostructural complexes, leading to a product distribution typical of OH. dominated oxidations, while Na4W10O32 (W10) and Na 12[WZn3(H2O)2(ZnW9O 34)2] (Zn5W19) exhibit a preferential reactivity towards uracil glycol. Kinetic studies and radical scavenger probes, performed on target intermediates and model diols, highlight a substantial difference in the mechanism of photocatalysis by the three complexes. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
One-pot production of phenazine from lignin-derived catechol
He, Zhimin,Qi, Wei,Ren, Tianyu,Yan, Ning
supporting information, p. 1224 - 1230 (2022/02/17)
Upgrading lignin-derived monomeric products is crucial in bio-refineries to effectively utilize lignin. Herein, we report a simple strategy to convert catechol to phenazine, a useful N-heterocycle three-aromatic-ring compound, whose current synthetic procedure is complex via a petroleum-derived feedstock. The reaction uses catechol as the sole carbon source and aqueous ammonia as reaction media and a nitrogen source. Without additional solvents, phenazine was obtained in 67% yield in the form of high purity crystals (>97%) over a Pd/C catalyst after a one-pot-two-stage reaction. When cyclohexane was used as a co-solvent in the first step, a higher yield (81%) and purity (>99%) were achieved. Mechanistic investigations involving control experiments and an isotope labeling study reveal that hydrogenation, amination, coupling and dehydrogenation reactions are the key steps leading to phenazine formation. The conversion of other lignin-derived catechols highlights that the protocol is extendable to produce substituted phenazines.
Catalytic Highly Regioselective C-H Oxygenation Using Water as the Oxygen Source: Preparation of 17O/18O-Isotope-Labeled Compounds
Doiuchi, Daiki,Uchida, Tatsuya
supporting information, p. 7301 - 7305 (2021/10/01)
We found that the oxygen atom of water is activated to iodosylbenzene derivatives via reversible hydrolysis of PhI(OOCR)2 and can be used to the oxygen source for ruthenium(bpga)-catalyzed site-selective C-H oxygenation. Ru(bpga)/PhI(OOCR)2/H2O system, sterically less bulky methinic and methylenic C-H bonds in various compounds can be converted to desired oxygen functional groups in a site-selective manner. Using this method, oxygen-isotope labeled compounds such as d-[3-17O/18O]-mannose can be prepared in a multigram scale.
