536-60-7Relevant academic research and scientific papers
COLEOSIDE, A MONOTERPENE GLYCOSIDE FROM COLEUS FORSKOHLII
Ahmed, Bahar,Vishwakarma, R. A.
, p. 3309 - 3310 (1988)
The alcoholic extract of the roots of Coleus forskohlii yielded caffeic acid and a new monoterpene glycoside, coleoside, characterised as cuminyl-O-β-D-glucopyranosyl(1->2)-β-D-galactopyranoside.Key Word Index - Coleus forskohlii; Labiatae; coleoside; cuminyl alcohol; caffeic acid.
Purification and properties of reductase of the three-component p-cymene methyl hydroxylase from Pseudomonas chlororaphis subsp. aureofaciens
Dutta, Tapan K.,Dutta, Arindam,Chakraborty, Joydeep,Sarkar, Jayita,Pal Chowdhury, Piyali,Gunsalus, Irwin C.
, p. 1263 - 1267 (2012)
A novel three-component p-cymene methyl hydroxylase from Pseudomonas chlororaphis subsp. aureofaciens was reported earlier on the basis of genetic characterization and their expression catalyzing methyl group hydroxylation. This enzyme system was inductively synthesized when grown on p-cymene and had an important role in initiating p-cymene metabolism in vivo. In the present study, a NADH-dependent cytochrome c reductase protein has been purified to an electrophoretically homogeneous state and found to be involved in the hydroxylation of methyl group of p-cymene. Molecular mass of the reductase appears to be 38 kDa by SDS/PAGE and 39 kDa by gel filtration apart from one molecule of tightly bound FAD and two atoms each of iron and acid-labile sulfur per molecule of the enzyme. An apparent Km value of the enzyme for NADH is 32 ± 1.2 μM. To the best of our knowledge, this is the first report on the purification of reductase component of p-cymene methyl hydroxylase.
Palladium complexes of anionic N-heterocyclic carbenes derived from sydnones in catalysis
Lücke, Ana-Luiza,Wiechmann, Sascha,Freese, Tyll,Guan, Zong,Schmidt, Andreas
, p. 643 - 650 (2016)
The anion of N-phenylsydnone, which can be generated on treatment of N-phenylsydnone with cyanomethyllithium without decomposition, can be represented as tripolar zwitterionic and as anionic N-heterocyclic carbene resonance forms. Its palladium complex was prepared from 4-bromo-3-phenylsydnone and tetrakis(triphenylphosphine)palladium and proved to be active as catalyst in Suzuki-Miyaura reactions. Thus, 2,5-dibromo-3,4-dinitrothiophene was effectively converted into 2,5-diaryl-3,4-dinitrothiophenes with 1-naphthyl, (4-trifluoromethoxy)phenyl, [4-(methylsulfanyl) phenyl], and biphenyl-4-yl boronic acid. 3-(Phenanthren-9-yl)quinoline was prepared by Suzuki-Miyaura reaction starting from 3-bromoquinoline. 1-Chloro-2,4-dinitrobenzene cross-coupled with phenyl boronic acid, 1-naphthyl boronic acid, 9-phenanthryl boronic acid. 4-Bromobenzylic alcohol gave (4-isopropylphenyl)methanol on sydnone-palladium complex-catalyzed reaction with isopropyl boronic acid.
Preparation method of P-isopropyl benzaldehyde and from isopropylbenzene
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, (2021/10/30)
The invention provides a method for preparing p-isopropylbenzaldehyde and from isopropylbenzaldehyde, and the preparation method comprises the following steps of: one step. The method comprises the following steps: adding cumene, an aldehyde solution, dropwise adding hydrochloric acid, heating to 80 - 88 °C after charging, and separating the phase to obtain the organic phase. The method comprises the following steps: uniformly mixing the inorganic base, the water and the phase transfer catalyst into a hydrolysis solution, adding the organic phase obtained in the step, and carrying out phase separation and purification under stirring to obtain p-isopropylbenzyl alcohol. Step III. The method comprises the following steps: adding hydrogen peroxide to isopropyl benzyl alcohol, a catalyst and a phase transfer catalyst obtained in the steps of oxidation and adding hydrogen peroxide, filtering and separating the filtrate to obtain crude aldehyde crude product and purifying to obtain p-propyl benzaldehyde. The preparation method has the advantages of being low in cost, good in process selectivity, mild in process condition and easy to realize industrialization.
Efficient and chemoselective hydrogenation of aldehydes catalyzed by well-defined PN3-pincer manganese(ii) catalyst precursors: An application in furfural conversion
Gholap, Sandeep Suryabhan,Dakhil, Abdullah Al,Chakraborty, Priyanka,Li, Huaifeng,Dutta, Indranil,Das, Pradip K.,Huang, Kuo-Wei
supporting information, p. 11815 - 11818 (2021/11/30)
Well-defined and air-stable PN3-pincer manganese(ii) complexes were synthesized and used for the hydrogenation of aldehydes into alcohols under mild conditions using MeOH as a solvent. This protocol is applicable for a wide range of aldehydes containing various functional groups. Importantly, α,β-unsaturated aldehydes, including ynals, are hydrogenated with the CC double bond/CC triple bond intact. Our methodology was demonstrated for the conversion of biomass derived feedstocks such as furfural and 5-formylfurfural to furfuryl alcohol and 5-(hydroxymethyl)furfuryl alcohol respectively.
Visible Light Induced Reduction and Pinacol Coupling of Aldehydes and Ketones Catalyzed by Core/Shell Quantum Dots
Xi, Zi-Wei,Yang, Lei,Wang, Dan-Yan,Feng, Chuan-Wei,Qin, Yufeng,Shen, Yong-Miao,Pu, Chaodan,Peng, Xiaogang
, p. 2474 - 2488 (2021/02/05)
We present an efficient and versatile visible light-driven methodology to transform aryl aldehydes and ketones chemoselectively either to alcohols or to pinacol products with CdSe/CdS core/shell quantum dots as photocatalysts. Thiophenols were used as proton and hydrogen atom donors and as hole traps for the excited quantum dots (QDs) in these reactions. The two products can be switched from one to the other simply by changing the amount of thiophenol in the reaction system. The core/shell QD catalysts are highly efficient with a turn over number (TON) larger than 4 × 104 and 4 × 105 for the reduction to alcohol and pinacol formation, respectively, and are very stable so that they can be recycled for at least 10 times in the reactions without significant loss of catalytic activity. The additional advantages of this method include good functional group tolerance, mild reaction conditions, the allowance of selectively reducing aldehydes in the presence of ketones, and easiness for large scale reactions. Reaction mechanisms were studied by quenching experiments and a radical capture experiment, and the reasons for the switchover of the reaction pathways upon the change of reaction conditions are provided.
Silica-coated Fe3O4 magnetic nanoparticles-supported sulfonic acid as a highly active and reusable catalyst in chemoselective deprotection of tert-butyldimethylsilyl (TBDMS) ethers
Hossein Javadi, Sayed,Zareyee, Daryoush,Monfared, Azam,Didehban, Khadijeh,Mirshokraee, Sayed Ahmmad
supporting information, p. 7 - 12 (2019/11/03)
Anchored propyl sulfonic acid on the surface of silica-coated magnetic nanoparticles (Fe3O4@SiO2@PrSO3H) was successfully employed in the deprotection of TBDMS ethers. The prepared magnetically separable nanocatalyst exhibited efficient catalytic activity with high conversion and selectivity in cleavage of TBDMS ethers. TBDMS ethers are efficiently cleaved to the corresponding hydroxyl compounds in methanol solution containing 2 mol% magnetic nano-catalysts. Good to excellent yields of products, simple work-up and product separation, selective cleavage of TBDMS ethers in the presence of TBDPS ethers, easy recycling of the catalyst with external magnet with no loss in its activity (7 reaction cycles) are important features of this new protocol.
Triazole derivative as well as preparation method and application thereof
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Paragraph 0053-0055; 0065-0067, (2020/06/09)
The invention relates to a triazole derivative as well as a preparation method and application thereof, which belong to the technical field of organic synthetic drugs. The structure of the triazole derivative is shown as a formula I. In the formula I, R1 and R2 are H, Cl, Br,-CF3,-CH(CH3)2 or -OCH3, and R1 and R2 are not H at the same time. R3 is -CH2 or -COCH2; X and Y are N or C, X and Y are not C at the same time, and X and Y are not N at the same time. The triazole derivative disclosed by the invention has a certain inhibition effect on germs of various crop diseases. Small toxic andside effects on plants are achieved. The preparation method of the triazole derivative is simple.
Diethylsilane as a Powerful Reagent in Au Nanoparticle-Catalyzed Reductive Transformations
Louka, Anastasia,Kidonakis, Marios,Saridakis, Iakovos,Zantioti-Chatzouda, Elisavet-Maria,Stratakis, Manolis
, p. 3508 - 3514 (2020/06/02)
Diethylsilane (Et2SiH2), a simple and readily available dihydrosilane, that exhibits superior reactivity, as compared to monohydrosilanes, in a series of reductive transformations catalyzed by recyclable and reusable Au nanoparticles (1 mol-%) supported on TiO2. It reduces aldehydes or ketones almost instantaneously at ambient conditions. It can be used in a one pot rapid reductive amination procedure, in which premixing of aldehyde and amine is required prior to the addition of the reducing agent and the catalyst, even in a protic solvent. An unprecedented method for the synthesis of N-arylisoindolines is also shown in the reductive amination between o-phthalaldehyde and anilines. In this transformation, it is proposed that the intermediate N,2-diphenylisoindolin-1-imines are reduced stepwise to the isoindolines. Finally, Et2SiH2 readily reduces amides into amines in excellent yields and shorter reaction times relative to previously known analogous nano Au(0)-catalyzed protocols.
Homoleptic Zinc-Catalyzed Hydroboration of Aldehydes and Ketones in the Presence of HBpin
Kumar, Gobbilla Sai,Harinath, Adimulam,Narvariya, Rajrani,Panda, Tarun K.
, p. 467 - 474 (2020/02/04)
Here, we report the reaction between N-phenyl-o-phenylenediamine and pyrrole-2-carboxaldehyde to afford the N-phenyl-o-phenyl-enediiminopyrrole ligand {L-H2} in quantitative yield. A one-pot reaction between {L-H2} and diethylzinc (ZnEt2) in a 2:1 ratio afforded the homoleptic zinc metal complex [{L-H}2Zn] (1). The solid-state structures of ligand {L-H2} and zinc complex 1 were confirmed using X-ray crystallography. Further, complex 1 was used for chemoselective hydroboration of aldehydes and ketones in the presence of pinacolborane (HBpin) at ambient temperature to produce the corresponding boronate esters in high yield.
