1125-21-9Relevant articles and documents
Selective aerobic oxidation of isophorone catalyzed by molybdovanadophosphate supported on carbon (NPMoV/C)
Hanyu, Atsushi,Sakurai, Yasunori,Fujibayashi, Shinya,Sakaguchi, Satoshi,Ishii, Yasutaka
, p. 5659 - 5662 (1997)
Isophorone was smoothly oxidized with molecular oxygen by molybdovanadophosphate supported on the active carbon ((NPMoV/C) to give 3-formyl-5,5-dimethyl-2-cyclohexen-1-one in relatively high selectivity. The regioselectivity of the oxidation by NPMoV/C was found to be just opposite to that of the conventional oxidations, The pore size of the supports appears to be an important factor governing the regioselectivity.
Selective synthesis of 4-hydroxyisophorone and 4-ketoisophorone by fungal peroxygenases
Aranda, Carmen,Municoy, Martí,Guallar, Víctor,Kiebist, Jan,Scheibner, Katrin,Ullrich, René,Del Río, José C.,Hofrichter, Martin,Martínez, Angel T.,Gutiérrez, Ana
, p. 1398 - 1405 (2019)
The recently discovered unspecific peroxygenases (UPOs) from the ascomycetes Chaetomium globosum and Humicola insolens were capable of selectively hydroxylating isophorone to 4-hydroxyisophorone (4HIP) and 4-ketoisophorone (4KIP), which are substrates of interest for the pharmaceutical and flavor-and-fragrance sectors. The model UPO from the basidiomycete Agrocybe aegerita was less regioselective, forming 7-hydroxyisophorone (and 7-formylisophorone) in addition to 4HIP. However, it was the most stereoselective UPO yielding the S-enantiomer of 4HIP with 88% ee. Moreover, using H. insolens UPO full kinetic resolution of racemic HIP was obtained within only 15 min, with >75% recovery of the R-enantiomer. Surprisingly, the UPOs from two other basidiomycetes, Marasmius rotula and Coprinopsis cinerea, failed to transform isophorone. The different UPO selectivities were rationalized by computational simulations, in which isophorone and 4HIP were diffused into the enzymes using the adaptive PELE software, and the distances from heme-bound oxygen in H2O2-activated enzyme to different substrate atoms, and the corresponding binding energies were analyzed. Interestingly, for process upscaling, full conversion of 10 mM isophorone was achieved with H. insolens UPO within nine hours, with total turnover numbers up to 5500. These biocatalysts, which only require H2O2 for activation, may represent a novel, simple and environmentally-friendly route for the production of isophorone derivatives.
Enhanced catalytic activity and selectivity in oxidation of α-isophorone to ketoisophorone with phosphomolybdic acid
Murphy,Schneider,Mallat,Baiker
, p. 547 - 549 (2001)
Aerobic allylic oxidation of α-isophorone with phosphomolybdic acid as catalyst in combination with DMSO and potassium tert-butoxide provides ketoisophorone in unprecedented high yield. This study suggests that the solvent can play a pivotal role in directing selectivity in allylic oxidations of highly substituted cyclic olefins.
Kinetics Study on Oxidation of β-Isophorone Using Molecular Oxygen
Chen, Zhirong,Fang, Tingting,Yuan, Shenfeng,Yin, Hong
, p. 295 - 303 (2016)
The oxidation kinetics of β-isophorone (β-IP) using molecular oxygen catalyzed by iron(III) acetylacetonate was investigated in a lab-scale agitator bubbling reactor. β-IP was found to give keto-isophorone (KIP) and 4-hydroxy-3,5,5-trimethyl-2-cyclohexen-1-one (HIP) along with little isomerization product α-isophorone (α-IP). The results show that the oxidation reaction took place in the pseudo-first-order fast reaction regime. The experiment was conducted under the mass transfer reaction regime as the mass transfer resistances could not be easily eliminated. The intrinsic kinetics was obtained through apparent kinetics. The activation energy of oxidation of β-IP to KIP is 70.5 ± 4.1 kJ mol-1, and the value of ln AKIP is 33.53 ± 1.22. Meanwhile, the activation energy of oxidation of β-IP to HIP is 86.4 ± 5.4 kJ mol-1 and the value of ln AHIP is 36.23 ± 1.52, which could provide theoretical basis for industrial design, amplification of reactor, and the optimization of reaction.
Combination of two catalytic sites in a novel nanocrystalline TiO 2-iron tetrasulfophthalocyanine material provides better catalytic properties
Beyrhouty, Mirvat,Sorokin, Alexander B.,Daniele, Stephane,Hubert-Pfalzgraf, Liliane G.
, p. 1245 - 1248 (2005)
Mesoporous titania nanocrystals containing iron tetrasulfophthalocyanine (FePcS) have been synthesised by a one-pot hydrolytic process from a modified Ti alkoxide; the novel hybrid catalyst was efficient in heterogeneous oxidation of 2,3,6-trimethylphenol and β-isophorone suggesting a cooperative effect between TiO2 and FePcS catalytic sites. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2005.
Oxidation-isomerization of an olefin to allylic alcohol using titania-silica and a base co-catalyst
Beck,Mallat,Baiker
, p. 79 - 87 (2000)
The allylic oxidation of olefins is essential in synthetic organic chemistry, affording valuable α,β-unsaturated alcohols and carbonyl compounds. Allylic oxidation maintains the olefinic functionality in the product, thereby allowing further useful transformations. The potential two-step, one-pot synthesis of α,β-unsaturated alcohols from olefins was illustrated on the example of 4-hydroxyisophorone using titania-silica aerogels and basic co-catalysts. Kinetic analysis of the complex reaction network revealed that titania-silica was efficient in the epoxidation of β-isophorone (3,5,5-trimethyl-3-cyclohexen-1-one) with tert-butylhydroperoxide at 353 K, whereas the acid/base-catalyzed in situ rearrangement to 4-hydroxy-isophorone (4-hydroxy-3,5,5-trimethyl-cyclohex-2-eonone) was slow. Addition of solid bases such as CaO, Na2CO3 and KF/CaF2 accelerated the rearrangement and achieved ≤ 77.5% selectivity at 83% conversion in 3 hr. Stronger bases K2CO3, BaO, Mg-Al-O-tBu, guanidine bases) inhibited the epoxidation reaction due to the deactivation of the isolated Ti sites and favored isomerization of β-isophorone to α-isophorone. Hydrophobization of titania-silica by covalently bound surface phenyl groups greatly suppressed oligomerization and isomerization of β-isophorone but did not improve selectivity to 4-hydroxyl-isophorone.
Method for continuously and efficiently preparing 2, 6, 6-trimethyl-2-cyclohexene-1, 4-diketone by oxidation
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Paragraph 0048-0054, (2019/04/09)
The invention discloses a method for continuously and efficiently preparing 2, 6, 6-trimethyl-2-cyclohexene-1, 4-diketone by oxidation. The method includes the steps: (1) performing reaction of raw material liquid and oxygen-containing gas in a spraying and mixing manner to obtain reaction liquid; (2) performing gas-liquid separation on the reaction liquid, adjusting temperature of a liquid phase,and performing reaction of the liquid phase and the oxygen-containing gas in a spraying and mixing manner to obtain reaction liquid; (3) repeating process of the step (2) until reaction is complete to obtain 2, 6, 6-trimethyl-2-cyclohexene-1, 4-diketone liquid. The oxygen-containing gas in the step (2) is a gas phase acquired by gas-liquid separation or newly prepared gas. The raw material liquidcomprises a catalyst, a reaction raw material and a solvent. By the aid of a gas and liquid mixing and spraying mode, the mixing effect of the reaction liquid, the gas and the catalyst is greatly superior to that of a mechanically stirred reactor, bubbles are more uniformly dispersed and sufficiently contact, ideal mass transfer effects are achieved, and reaction is accelerated.
Combining Photo-Organo Redox- and Enzyme Catalysis Facilitates Asymmetric C-H Bond Functionalization
Zhang, Wuyuan,Fueyo, Elena Fernandez,Hollmann, Frank,Martin, Laura Leemans,Pesic, Milja,Wardenga, Rainer,H?hne, Matthias,Schmidt, Sandy
supporting information, p. 80 - 84 (2019/01/04)
In this study, we combined photo-organo redox catalysis and biocatalysis to achieve asymmetric C–H bond functionalization of simple alkane starting materials. The photo-organo catalyst anthraquinone sulfate (SAS) was employed to oxyfunctionalise alkanes to aldehydes and ketones. We coupled this light-driven reaction with asymmetric enzymatic functionalisations to yield chiral hydroxynitriles, amines, acyloins and α-chiral ketones with up to 99 % ee. In addition, we demonstrate functional group interconversion to alcohols, esters and carboxylic acids. The transformations can be performed as concurrent tandem reactions. We identified the degradation of substrates and inhibition of the biocatalysts as limiting factors affecting compatibility, due to reactive oxygen species generated in the photocatalytic step. These incompatibilities were addressed by reaction engineering, such as applying a two-phase system or temporal and spatial separation of the catalysts. Using a selection of eleven starting alkanes, one photo-organo catalyst and 8 diverse biocatalysts, we synthesized 26 products and report for the model compounds benzoin and mandelonitrile > 97 % ee at gram scale.
