765-87-7Relevant academic research and scientific papers
OMS-2 nanorod-supported cobalt catalyst for aerobic dehydrocyclization of vicinal diols and amidines: Access to functionalized imidazolones
Xie, Feng,Chen, Xiuwen,Zhang, Xiangyu,Luo, Chujun,Lin, Shizhuo,Chen, Xiaoyong,Li, Bin,Li, Yibiao,Zhang, Min
, p. 192 - 197 (2021/05/17)
The development of reusable base metal catalysts for innovative catalytic transformations is a key technology toward sustainable production of fine chemicals, pharmaceuticals, and other function products. Herein, we report the preparation of a new highly dipersed manganese oxides of octahedral molecular sieve (OMS-2) nanorod-supported cobalt catalyst, which is successfully applied for aerobic dehydrocyclization of vicinal diols and amidines to access structurally diverse imidazolones, a class of valuable compounds found in numerous natural and biomedical products. The developed catalytic transformation proceeds with broad substrate scope, good functional group compability, the use of green molecular oxygen and reusable cobalt catalyst, which offers an important platform for the conversion of abundant and sustainable alcohol resources into functional N-heterocycles. The strategy combining nanocatalyst design with aerobic dehydrocoupling is anticipated to achieve other challenging catalytic transformations.
Preparation method 1 and 2 - cyclohexanedione
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Paragraph 0048; 0052; 0055; 0059; 0064; 0065; 0069; 0079, (2021/11/10)
The invention belongs to the technical field of chemical synthesis and particularly relates to a preparation method of 1-2 - cyclohexanedione. The invention provides 1-2 - Cyclohexanedione preparation method which comprises the following steps: cyclohexanone. The bromo reagent, the basic catalyst and the polar organic solvent are mixed for bromination reaction to obtain 2, 6 - dibromocyclohexanone. The mixture of 2, 6 - dibromocyclohexanone, inorganic base and polar solvent is subjected to hydrolysis reaction to obtain the 1, 2 -cyclohexanedione. To the preparation method, cyclohexanone and bromination reagent are taken as raw materials, 1 and 2 - cyclohexanedione with high yield and high purity can be prepared by sequentially conducting bromination reaction and hydrolysis reaction, and the preparation method provided by the invention is simple and easy to obtain and suitable for industrial production.
Bioinspired oxidation of oximes to nitric oxide with dioxygen by a nonheme iron(II) complex
Bhattacharya, Shrabanti,Lakshman, Triloke Ranjan,Sutradhar, Subhankar,Tiwari, Chandan Kumar,Paine, Tapan Kanti
, p. 3 - 11 (2019/11/11)
The ability of two iron(II) complexes, [(TpPh2)FeII(benzilate)] (1) and [(TpPh2)(FeII)2(NPP)3] (2) (TpPh2 = hydrotris(3,5-diphenylpyrazol-1-yl)borate, NPP-H = α-isonitrosopropiophenone), of a monoanionic facial N3 ligand in the O2-dependent oxidation of oximes is reported. The mononuclear complex 1 reacts with dioxygen to decarboxylate the iron-coordinated benzilate. The oximate-bridged dinuclear complex (2), which contains a high-spin (TpPh2)FeII unit and a low-spin iron(II)–oximate unit, activates dioxygen at the high-spin iron(II) center. Both the complexes exhibit the oxidative transformation of oximes to the corresponding carbonyl compounds with the incorporation of one oxygen atom from dioxygen. In the oxidation process, the oxime units are converted to nitric oxide (NO) or nitroxyl (HNO). The iron(II)–benzilate complex (1) reacts with oximes to afford HNO, whereas the iron(II)–oximate complex (2) generates NO. The results described here suggest that the oxidative transformation of oximes to NO/HNO follows different pathways depending upon the nature of co-ligand/reductant.
FeCl3-Promoted ring size-dictating diversity-oriented synthesis (DOS) of N-heterocycles using: In situ -generated cyclic imines and enamines
Dhandabani, Ganesh Kumar,Mutra, Mohana Reddy,Wang, Jeh-Jeng
supporting information, p. 7542 - 7545 (2019/07/04)
The FeCl3-promoted ring size-controlled oxidative activation of o-alkynylanilines opens up a complementary appealing protocol for poly-N-heterocycle synthesis. When electron-poor π-alkyne iron species combine with cyclic enamines obtained from cyclohexanone and β-tetralone, they undergo a regioselective 6-exo-dig cyclization to afford the corresponding dibenzo[b,j][1,10]phenanthrolines and 12-benzoylated dihydrobenzo[a]acridine skeletons. Later, these acridine motifs become completely unsaturated due to dehydrogenative aromatization via the aza-allyl oxidation intermediate. We obtained all quaternary carbon centre pseudoindoxyls through the Mannich-type alkylation of 2,3-dihydro-1H-inden-1-one with cyclic ketimines generated from the in situ intramolecular nucleophilic cyclization of o-alkynylanilines.
Ultrafast synthesis of nanosized Ti-Beta as an efficient oxidation catalyst: Via a structural reconstruction method
Wang, Bowen,Xu, Hao,Zhu, Zhiguo,Guan, Yejun,Wu, Peng
, p. 1857 - 1866 (2019/04/29)
As a representative selective oxidation titanosilicate catalyst, a Ti-Beta zeolite is less used in comparison with TS-1, Ti-MWW and Ti-MOR, mostly due to its high hydrophilicity originating from a BEA? intergrowth framework. A novel recrystallization method was proposed in the present study to prepare highly hydrophobic Ti-Beta with nanosized crystals (90 nm), high Ti content (Si/Ti = 20) and intercrystal mesoporosity. The fluoride-assisted recrystallization was realized quickly by dissolving extensively a dealuminated Beta zeolite in a mixture of a tetraethylammonium aqueous solution and Ti precursor, producing highly crystalline Ti-Beta in an extremely short time of 1 h. The obtained Ti-Beta zeolite exhibited superior catalytic activity in the liquid-phase epoxidation reactions of bulky alkenes like cyclohexene with hydrogen peroxide or tert-butyl hydroperoxide as an oxidant, compared to those Ti-Beta catalysts prepared by conventional hydrothermal or secondary synthesis routes.
Method for synthesizing 1,2-cyclohexanedione
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Paragraph 0014; 0020-0037, (2018/12/13)
The invention relates to a method for synthesizing 1,2-cyclohexanedione. The method comprises the following steps: dissolving cyclohexanone into a mixed system of an organic solvent and water, furtheradding iodine of a catalysis amount, carrying out a reaction for 1-2 hours at 25-80 DEG C, carrying out vacuum distillation on the obtained crude product, thereby obtaining the 1,2-cyclohexanedione,wherein the volume ratio of the organic solvent to water in the mixed system is (1:1) to (1:10). As low-toxicity and low-harm raw materials are used, no toxic or harmful waste gas or waste dreg is generated in the whole reaction process, in addition, the method is simple to operate and high in product yield, and the product cost is effectively reduced. Compared with the prior art, the method provided by the invention is applicable to on-scale industrial production.
Copper based coordination polymers based on metalloligands: Utilization as heterogeneous oxidation catalysts
Kumar, Gulshan,Hussain, Firasat,Gupta, Rajeev
, p. 16985 - 16994 (2019/01/03)
This work presents the synthesis and characterization of two Cu(ii)-based coordination polymers prepared by utilizing two different Co(iii)-based metalloligands offering appended arylcarboxylic acid groups. Both coordination polymers are three-dimensional in nature and present pores and channels filled with water molecules. Both coordination polymers function as heterogeneous catalysts for the epoxidation of various olefins using O2 while employing isobutyraldehyde as the coreductor and for peroxide-mediated oxidation of assorted benzyl alcohols. The catalytic results illustrate efficient oxidation reactions, whereas the hot-fltration test and leaching experiments indicate the true heterogeneous nature of the catalysis.
Organic intermediates in the synthesis of 1, 6 - Cyclohexanedione (by machine translation)
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Paragraph 0014; 0016-0027, (2018/07/30)
The invention disclosed is intermediate in 1, 6 - Cyclohexanedione synthetic method, comprises the following steps: in the reaction container by adding 2 - methoxy - cyclohexanone, nitrile-butadiene solution, control solution temperature, maintain, then adding dimethyl sulfoxide solution, the stirring speed is, to continue the reaction; raising the temperature, adding the sodium nitrate solution, platinum tetrachloride powder, reaction, for methylamine solution reflux extraction, the combined extract, adding potassium sulfate in the solution, the solution is layered, hexyl ether solution for washing, recrystallization in the pentaerythritol solution, desiccant dehydration, to get the finished product 1, 6 - Cyclohexanedione. (by machine translation)
Oxidative C?C Cleavage of Ketols over Vanadium–Carbon Catalysts
Nakagawa, Yoshinao,Sekine, Dai,Obara, Naoyuki,Tamura, Masazumi,Tomishige, Keiichi
, p. 3412 - 3419 (2017/09/06)
The oxidation of 2-hydroxycyclohexanone and carbohydrates to adipic acid and formic acid, respectively, was performed with a combination of a vanadium catalyst, carbon as the cocatalyst, and O2 in water under mild conditions (353 K, 0.1–0.3 MPa). The catalytic activity of aqueous V2O5 was increased significantly by the addition of activated carbon (C), whereas the addition of carbon black, graphene oxide, and carbon nanotubes has a much smaller effect. UV/Vis and inductively coupled plasma optical emission spectroscopy were used to show that most VV species are adsorbed on C at least in a short reaction time. The VIV species (VO2+) was not adsorbed on C. The order of activity of vanadium species was VV on C>dissolved free VV?dissolved free VIV. To help the oxidation of VIV, the further addition of phosphomolybdate (PMo12O40 3?; PMo) was also tested, and the activity was improved. The selectivity and yield of adipic acid from 2-hydroxycyclohexanone was also improved slightly by the addition of PMo. However, in the oxidation of glucose, the addition of PMo did not improve the final formic acid yield. The oxidation of glucose with the V+C system gave a 42 % yield of formic acid, which was comparable to the values reported with a more expensive PVMo polyoxometalate catalyst. A reaction mechanism is proposed in which the reversibly formed “biradical” state of the vanadium ketol complex reacts with O2 and accompanying rearrangement dissociates the C?C bond.
Copper(ii) and iron(iii) complexes with arylhydrazone of ethyl 2-cyanoacetate or formazan ligands as catalysts for oxidation of alcohols
Martins, Nuno M. R.,Mahmudov, Kamran T.,Guedes Da Silva, M. Fátima C.,Martins, Luísa M. D. R. S.,Pombeiro, Armando J. L.
supporting information, p. 10071 - 10083 (2016/12/07)
The aquasoluble [Cu(1κN,O2:2κO-HL1)(S)]2 [S = CH3OH (1), (CH3)2NCHO (2)] and [Cu(κN-HL1)(en)2]·CH3OH·H2O (3) CuII complexes were prepared by the reaction of CuII nitrate hydrate with the new ligand (E/Z)-4-(2-(1-cyano-2-ethoxy-2-oxoethylidene)hydrazinyl)-3-hydroxybenzoic acid (H3L1), in the presence (for 3) or absence (for 1 and 2) of ethylenediamine (en), while the FeIII complex [Fe(κN3-HL2)2] (4) was isolated by treatment of iron(III) chloride hexahydrate with the new ligand (1E,1E)-N′,2-di(1H-1,2,4-triazol-3-yl)diazenecarbohydrazonoyl cyanide (H3L2), and characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. Cooperative E,Z → E isomerization of H3L1, induced by coordination and ionic interactions, occurs upon interaction with CuII in the presence of en. Complexes 1-4 act as catalyst precursors for the solvent-free microwave (MW) assisted selective oxidation of primary or secondary alcohols and diols to the corresponding aldehydes, ketones and diketones, respectively, with yields in the 5-99% range (TONs up to 4.96 × 102) after 60 min of MW irradiation at 120 °C. The influence of temperature, time and organic radicals was studied and also the regioselective oxidation of the catalytic systems involving the primary and secondary alcohols.
