405197-74-2Relevant articles and documents
Poisoning titration of metal nickel-based catalysts – an efficient and convenient tool to quantify active sites in transfer hydrogenation
Philippov, Alexey A.,Chibiryaev, Andrey M.,Yakushkin, Stanislav S.,Gladky, Alexey Yu.,Martyanov, Oleg N.
, (2021)
For the first time, the poisoning effect of 15 different chemical compounds on Raney nickel catalyst has been comparatively studied in the transfer hydrogenation of camphor using 2-PrOH as a solvent and a hydrogen donor. It has been shown that thiophenol, HCl and H3PO4 demonstrate the strongest poisoning action under the reaction conditions: no camphor conversion was observed at 5 mol.% of poison-to-nickel ratio. A strong chemical binding of thiophenol molecules to the catalyst surface without C–S bond cleavage was proved by XRF, TPD methods, CHNS analysis, and FTIR spectroscopy. It was shown that the poisoning titration with thiophenol is an effective and convenient tool to calculate the number of active sites for Ni based catalysts directly, measuring catalytic activity in target chemical reaction, which was defined correspondently as 2.4 h?1 and 9.6 × 10–5 mole for Raney nickel catalyst in the transfer hydrogenation.
Synthesis method of compound
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Paragraph 0027-0030, (2020/07/24)
The invention discloses a preparation method of 1, 7, 7-trimethyl bicyclo[2, 2, 1]-2, 5-heptadiene-2, 5-bis(trifluoromethanesulfonic acid), namely a compound 1. 1, 7, 7-trimethyl bicyclo[2, 2, 1]-2, 5-heptadione and N-phenylbis(trifluoromethanesulfonamide)imine are taken as raw materials, reacting is performed under the action of alkali to generate a compound 1 reaction solution, after the reaction is finished, quenching with acid water is performed, standing for layering are performed, and an organic phase is concentrated under reduced pressure until the organic phase is dry to obtain a compound 1 finished product. According to the method, the defect that the reaction needs to be carried out at the extremely low temperature of-78 DEG C is overcome, the reaction temperature is increased to-30 DEG C to-15 DEG C, and common refrigeration equipment can meet the production requirement. Acid water quenching is adopted for post-treatment, so that the stability of the product in the concentration process is improved. The method is simple and convenient to operate, and less three wastes are discharged. The synthesis process is simple and convenient to operate, high in production efficiency, low in cost, energy-saving, emission-reducing, environment-friendly and suitable for industrial mass production.
Purification method of compound
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Paragraph 0019-0022, (2020/07/24)
The invention discloses a purification method of a compound. The purification method of (R, R)-2, 5-bis(4-fluorophenyl)-1, 7, 7-trimethyl bicyclo[2, 2, 1]-2, 5-heptadiene comprises the following steps: by taking 2-methyltetrahydrofuran and water as reacti
Method for preparing borneol by saponification of borneol acetate catalyzed by solid super-strong base
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Paragraph 0028-0033, (2020/02/29)
The invention relates to a method for preparing borneol by saponification of borneol acetate catalyzed by solid super-strong alkali. The saponification reaction can be carried out under the conditionof temperature by adopting solid super-strong alkali as catalyst, the conversion rate of borneol acetate is above 99%, and the content of product borneol is high, above 99.2%.
Simple H2-free hydrogenation of unsaturated monoterpenoids catalyzed by Raney nickel
Philippov, Alexey A.,Chibiryaev, Andrey M.,Martyanov, Oleg N.
, p. 380 - 381 (2019/08/20)
A series of monoterpenoids (citral, carvone, menthone, camphor) as well as cyclohexanone and hex-5-en-2-one were subjected to transfer hydrogenation with PriOH/Raney nickel system at 82 or 150 °C. Among monoterpenoids, citral and carvone underwent full conversion at 82 °C within 5 h.
Flat and Efficient H CNN and CNN Pincer Ruthenium Catalysts for Carbonyl Compound Reduction
Giboulot, Steven,Baldino, Salvatore,Ballico, Maurizio,Figliolia, Rosario,P?thig, Alexander,Zhang, Shuanming,Zuccaccia, Daniele,Baratta, Walter
, p. 1127 - 1142 (2019/03/14)
The bidentate HCNN dicarbonyl ruthenium complexes trans,cis-[RuCl2(HCNN)(CO)2] (1-3) and trans,cis-[RuCl2(ampy)(CO)2] (1a) were prepared by reaction of [RuCl2(CO)2]n with 1-[6-(4′-methylphenyl)pyridin-2-yl]methanamine, benzo[h]quinoline (HCNN), and 2-(aminomethyl)pyridine (ampy) ligands. Alternatively, the derivatives 1-3 were obtained from the reaction of RuCl3 hydrate with HCO2H and HCNN. The pincer CNN cis-[RuCl(CNN)(CO)2] (4) was isolated from 1 by reaction with NEt3. The monocarbonyl complexes trans-[RuCl2(HCNN)(PPh3)(CO)] (5-7) were synthesized from [RuCl2(dmf)(PPh3)2(CO)] and HCNN ligands, while the diacetate trans-[Ru(OAc)2(HCNN)(PPh3)(CO)] (8) was obtained from [Ru(OAc)2(PPh3)2(CO)]. Carbonylation of cis-[RuCl(CNN)(PPh3)2] with CO afforded the pincer derivatives [RuCl(CNN)(PPh3)(CO)] (9-11). Treatment of 9 with Na[BArf]4 and PPh3 gave the cationic complex trans-[Ru(CNN)(PPh3)2(CO)][BArf4] (12). The dicarbonyl derivatives 1-4, in the presence of PPh3 or PCy3, and the monocarbonyl complexes 5-12 catalyzed the transfer hydrogenation (TH) of acetophenone (a) in 2-propanol at reflux (S/C = 1000-100000 and TOF up to 100000 h-1). Compounds 1-3, with PCy3, and 6 and 8-10 were proven to catalyze the TH of carbonyl compounds, including α,β-unsaturated aldehydes and bulky ketones (S/C and TOF up to 10000 and 100000 h-1, respectively). The derivatives 1-3 with PCy3 and 5 and 6 catalyzed the hydrogenation (HY) of a (H2, 30 bar) at 70 °C (S/C = 2000-10000). Complex 5 was active in the HY of diaryl ketones and aryl methyl ketones, leading to complete conversion at S/C = 10000.
Unexpected reactivity of 2-fluorolinalyl diphosphate in the active site of crystalline 2-methylisoborneol synthase
Koeksal, Mustafa,Chou, Wayne K. W.,Cane, David E.,Christianson, David W.
, p. 5247 - 5255 (2013/09/02)
The crystal structure of 2-methylisoborneol synthase (MIBS) from Streptomyces coelicolor A3(2) has been determined in its unliganded state and in complex with two Mg2+ ions and 2-fluoroneryl diphosphate at 1.85 and 2.00 A resolution, respectively. Under normal circumstances, MIBS catalyzes the cyclization of the naturally occurring, noncanonical 11-carbon isoprenoid substrate, 2-methylgeranyl diphosphate, which first undergoes an ionization-isomerization-ionization sequence through the tertiary diphosphate intermediate 2-methyllinalyl diphosphate to enable subsequent cyclization chemistry. MIBS does not exhibit catalytic activity with 2-fluorogeranyl diphosphate, and we recently reported the crystal structure of MIBS complexed with this unreactive substrate analogue [ Koeksal, M., Chou, W. K. W., Cane, D. E., Christianson, D. W. (2012) Biochemistry 51, 3011-3020 ]. However, cocrystallization of MIBS with the fluorinated analogue of the tertiary allylic diphosphate intermediate, 2-fluorolinalyl diphosphate, reveals unexpected reactivity for the intermediate analogue and yields the crystal structure of the complex with the primary allylic diphosphate, 2-fluoroneryl diphosphate. Comparison with the structure of the unliganded enzyme reveals that the crystalline enzyme active site remains partially open, presumably due to the binding of only two Mg2+ ions. Assays in solution indicate that MIBS catalyzes the generation of (1R)-(+)-camphor from the substrate 2-fluorolinalyl diphosphate, suggesting that both 2-fluorolinalyl diphosphate and 2-methyllinalyl diphosphate follow the identical cyclization mechanism leading to 2-substituted isoborneol products; however, the initially generated 2-fluoroisoborneol cyclization product is unstable and undergoes elimination of hydrogen fluoride to yield (1R)-(+)-camphor.
Selective hydrosilylation of ketones catalyzed by in situ -generated iron NHC complexes
Buitrago, Elina,Zani, Lorenzo,Adolfsson, Hans
experimental part, p. 748 - 752 (2012/01/05)
Aryl alkyl-, heteroaryl alkyl- and dialkyl ketones were readily reduced to their corresponding secondary alcohols in high yields, using the commercially available and inexpensive polymeric silane polymethylhydrosiloxane (PMHS), as reducing agent. The reaction is catalyzed by an in situ-generated iron complex, conveniently generated from iron(II) acetate and the commercially available N-heterocyclic carbene (NHC) precursor IPr·HCl.
Metal complexes-catalyzed hydrolysis and alcoholysis of organic substrates and their application to kinetic resolution
Tokunaga, Makoto,Aoyama, Hiroshi,Kiyosu, Junya,Shirogane, Yuki,Iwasawa, Tetsuo,Obora, Yasushi,Tsuji, Yasushi
, p. 472 - 480 (2008/02/06)
Metal complexes-catalyzed hydrolysis and alcoholysis of organic substrates such as alkenyl esters, alkenyl ethers, and azlactones (oxazol-5(4H)-ones) are described. These reactions were applied for kinetic resolution of chiral compounds and high selectivities were achieved with vinyl ethers of 2-substituted cyclohexanols, 1,1′-bi-2-naphthols, 1,1′-bi-2-phenols, and 4,4-disubstituted azlactones. Oxidative carbon-carbon bond cleavage reactions, which were found in the course of the study of asymmetric hydrolysis were also described.
Modified hydroborate agent: (2,2′-bipyridyl)(tetrahydroborato)zinc complex, [Zn(BH4)2(bpy)], as a new, stable, efficient ligand-metal hydroborate and chemoselective reducing agent
Zeynizadeh, Behzad
, p. 317 - 326 (2007/10/03)
(2,2′-Bipyridyl)(tetrahydroborato)zinc complex, [Zn(BH4)2(bpy)], is a new white stable compound which has been used for efficient reduction of variety of carbonyl compounds such as aldehydes, ketones, acyloins, α-diketones and α, β-unsaturated carbonyl compounds (1,2-reduction) to their corresponding alcohols in acetonitrile at room temperature. Excellent chemoselectivity was also observed for the reduction of aldehydes over ketones with this reducing agent.