100-06-1Relevant articles and documents
Regeneration of carbonyl compounds by oxidative cleavage of oximes with NBS in the presence of β-cyclodextrin in water
Reddy, M. Somi,Narender,Rao, K. Rama
, p. 3875 - 3881 (2004)
The conversion of different oximes to the corresponding carbonyl compounds was carried out at room temperature in good to high yields with N-bromosuccinimide in water in the presence of β-cyclodextrin.
First example of water-soluble transition-metal catalysts for Oppenauer-type oxidation of secondary alcohols
Ajjou, Abdelaziz Nait
, p. 13 - 16 (2001)
The first water-soluble transition-metal catalysts for Oppenauer-type oxidation of secondary alcohols have been developed. The catalytic system composed of [Ir(COD)Cl]2, 2,2'-biquinoline-4,4'-dicarboxylic acid dipotassium salt (BQC) and sodium carbonate is highly efficient for the selective oxidation of benzylic and aliphatic secondary alcohols to the corresponding ketones with catalyst/substrate ratios ranging from 0.4 to 2.5 percent. The substitution of [Ir(COD)Cl]2 by its rhodium analog [Rh(COD)Cl]2 generates a less active catalytic system. [Ir(COD)Cl]2/BQC was also found to be more active than its water-insoluble analog system [Ir(COD)Cl]2/2,2'-biquinoline (BC).
A Mild and Efficient Oxidation of Alcohols to Ketones with Iodosobenzene/(Salen) Manganese Complex
Kim, Sung Soo,Borisova, Galina
, p. 3961 - 3967 (2003)
An excellent method for the chemoselective oxidation of alcohols to ketones with C6H5IO catalyzed by (salen) manganese/4A MS in CH3CN has been devised. The reported procedure is fast, simple, and the yields are excellent (> 95%) in most cases.
TEMPO-tert-butyl nitrite: An efficient catalytic system for aerobic oxidation of alcohols
He, Xijun,Shen, Zhenlu,Mo, Weimin,Sun, Nan,Hu, Baoxiang,Hu, Xinquan
, p. 89 - 92 (2009)
A metal-free catalytic system consisting of 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and tert-butyl nitrite has been developed to activate molecular oxygen for the aerobic oxidation of alcohols. A variety of active and non-active alcohols were oxidized to their corresponding carbonyl compounds in high selectivity and yields.
Enantiocomplementary C–H Bond Hydroxylation Combining Photo-Catalysis and Whole-Cell Biocatalysis in a One-Pot Cascade Process
Peng, Yongzhen,Li, Danyang,Fan, Jiajie,Xu, Weihua,Xu, Jian,Yu, Huilei,Lin, Xianfu,Wu, Qi
, p. 821 - 825 (2020)
Enantiocomplementary hydroxylation of alkyl aromatics through a one-pot photo-biocatalytic cascade reaction is described. The photoredox process is implemented in aqueous phase with O2 as oxidant and the subsequent (R)- or (S)-selective bioreduction is performed by whole cell system without the addition of the expensive cofactor (NADPH). This mild, operationally simple protocol transforms a wide variety of readily available aromatic compounds into valuable chiral alcohols with high yield (up to 90 %) and stereoselectivity (up to 99 %), thereby displaying important potentials in organic synthesis.
Catalytic Friedel-Crafts acylation of alkoxybenzenes mediated by aluminum hydrogensulfate in solution and solvent-free conditions
Salehi, Peyman,Khodaei, Mohammad Mehdi,Zolfigol, Mohammad Ali,Sirouszadeh, Sara
, p. 1863 - 1864 (2003)
Friedel-Crafts acylation of alkoxybenzenes was achieved efficiently by a reaction with aliphatic acid anhydrides in the presence of catalytic amounts of aluminum hydrogensulfate, Al(HSO4)3, in nitromethane and under solvent-free conditions. Alkylbenzenes and aryl halides, as well as aromatic anhydrides, remained intact under these conditions.
A Novel Catalyst System, Antimony(V) Chloride-Lithium Perchlorate (SbCl5-LiClO4), in the Friedel-Crafts Acylation Reaction
Mukaiyama, Teruaki,Suzuki, Kaoru,Han, Jeong Sik,Kobayashi, Shu
, p. 435 - 438 (1992)
A novel catalyst system consisting of antimony(V) chloride (SbCl5) and lithium perchlorate (LiClO4) effectively promotes the Friedel-Crafts acylation reaction of aromatic compounds with acid anhydrides.
A supported manganese complex with amine-bis(phenol) ligand for catalytic benzylic C(sp3)-H bond oxidation
Karimpour, Touraj,Safaei, Elham,Karimi, Babak
, p. 14343 - 14351 (2019)
With regards to the importance of direct and selective activation of C-H bonds in oxidation processes, we develop a supported manganese amine bis(phenol) ligand complex as a novel catalyst with the aim of obtaining valuable products such as carboxylic acids and ketones that have an important role in life, industry and academic laboratories. We further analyzed and characterized the catalyst using the HRTEM, SEM, FTIR, TGA, VSM, XPS, XRD, AAS, and elemental analysis (CHN) techniques. Also, the catalytic evaluation of our system for direct oxidation of benzylic C-H bonds under solvent-free condition demonstrated that the heterogeneous form of our catalyst has high efficiency in comparison with homogeneous ones due to more stability of the supported complex. Furthermore, the structural and morphological stability of our efficient recyclable catalytic system has been investigated and all of the data proved that the complex was firmly anchored to the magnetite nanoparticles.
N- Hydroxyphthalimide and transition metal salts as catalysts of the liquid-phase oxidation of 1-methoxy-4-(1-methylethyl)benzene with oxygen
Orlinska, Beata,Romanowska, Iwona
, p. 670 - 676 (2011)
The oxidation process of 1-methoxy-4-(1-methylethyl)benzene catalysed by N-hydroxyphthalimide (NHPI) or NHPI in combination with Cu(II), Co(II), Mn(II) and Fe(II) salts was studied. The effects of the amount of catalyst and the temperature were determined
Solid state cleavage of oximes with potassium permanganate supported on alumina
Imanzadeh,Hajipour,Mallakpour
, p. 735 - 740 (2003)
A manipulatively simple and rapid method for conversion of oximes to the corresponding carbonyl compounds is described. The reaction is conducted under solvent-less conditions using alumina-supported permanganate. According to the reaction system and conditions used, different ketones and aldehydes are obtained in moderate and good yields.
p-Methoxyphenacyl Esters as Photodeblockable Protecting Groups for Phosphates
Epstein, William W.,Garrossian, Massoud
, p. 532 - 533 (1987)
p-Methoxyphenacyl esters of substituted phosphates have been found to be photosensitive protecting groups which may be useful in biologically important phosphate synthesis.
Reactions of silica chloride (SiO2Cl)/DMSO, a heterogeneous system for the facile regeneration of carbonyl compounds from thioacetals and ring-expansion annelation of cyclic thioacetals
Firouzabadi, Habib,Iranpoor, Nasser,Hazarkhani, Hassan,Karimi, Babak
, p. 2572 - 2576 (2002)
Silica chloride (SiO2Cl)/DMSO, as a heterogeneous system, has been efficiently used for deprotection of thioacetals into aldehydes in dry CH2Cl2 at room temperature. Thioketals without enolizable hydrogens adjacent to a sulfur atom are converted easily to the corresponding ketones in high yields under similar reaction conditions. However, thioketals with enolizable methyl and methylene groups undergo ring-expansion reactions to afford 1,4-dithiepins and 1,4-dithiins in dry CH2Cl2 at room temperature in good yields.
VO(acac)2 catalyzed oxidative deprotection of oximes, hydrazones, and semicarbazones
De, Surya Kanta
, p. 4409 - 4415 (2004)
Oximes, hydrazones, and semicarbazones undergo facile deprotection in the presence of a catalytic amount of vanadyl acetylacetonate and hydrogen peroxide in acetone at room temperature.
Biphasic copper-catalyzed C–H bond activation of arylalkanes to ketones with tert-butyl hydroperoxide in water at room temperature
Hossain, Md. Munkir,Shyu, Shin-Guang
, p. 4252 - 4257 (2016)
A facile C–H bond activation of arylalkanes to their corresponding ketones catalyzed by copper salts using tert-butyl hydroperoxide as an oxidant in water at room temperature is described. Easy product separation, simple reaction procedures (without using base or phase transfer catalysis), and catalyst recycling make the catalytic system attractive. It is also active beyond activated benzylic methylene positions and could tolerate factionalized arylalkanes with diverse groups.
Three Pd-decavanadates with a controllable molar ratio of Pd to decavanadate and their heterogeneous aerobic oxidation of benzylic C-H bonds
Huang, Xianqiang,Li, Jikun,Shen, Guodong,Xin, Nana,Lin, Zhengguo,Chi, Yingnan,Dou, Jianmin,Li, Dacheng,Hu, Changwen
, p. 726 - 733 (2017)
By the combination of Pd-complexes and [V10O28]6-, three Pd-decavanadate compounds [Pd(NH3)4]3[V10O28]·8H2O (1), [Pd(deta)(H2O)]2(NH4)2[V10O28]·2H2O (2) (deta = diethylenetriamine) and [Pd(dpa)2](Hdpa)2(Et3NH)2[V10O28]·2H2O (3) (dpa = 2,2′-dipyridylamine) have been successfully synthesized and thoroughly characterized using single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR) and elemental analyses (EA). Interestingly, in the three compounds, the molar ratios of Pd to decavanadate vary from 3:1 to 1:1 by changing N-ligands. The three Pd-decavanadates as heterogeneous catalysts are active in the aerobic oxidation of benzylic hydrocarbons under solvent-free conditions without adding any additives and co-catalysts. Moreover, compound 1 can be reused three times without losing its activity.
Hydration of aromatic alkynes catalyzed by a self-assembled hexameric organic capsule
La Sorella, Giorgio,Sperni, Laura,Ballester, Pablo,Strukul, Giorgio,Scarso, Alessandro
, p. 6031 - 6036 (2016)
The combination of a Br?nsted acid catalyst and a supramolecular organic capsule formed by the self-assembly of six resorcin[4]arene units efficiently promotes the mild hydration of aromatic alkynes to their corresponding ketones. The capsule provides a suitable nanoenvironment that favors protonation of the substrate and addition of water.
Hydration of terminal alkynes catalyzed by a water-soluble salen-Co(III) complex
Wang, Shoufeng,Miao, Chengxia,Wang, Wenfang,Lei, Ziqiang,Sun, Wei
, p. 1695 - 1700 (2014)
A water-soluble salen-Co(III) complex was studied as catalyst for hydration of terminal alkynes to methyl ketones in the presence of H2SO4 as a co-catalyst. The products were obtained with excellent yields using relatively low catalyst loadings and a simple protocol. Notably, the products were easily separated from the catalyst after reaction by extraction, and the catalyst could be recovered and reused with only a slight loss of activity.
A well-defined complex for palladium-catalyzed aerobic oxidation of alcohols: Design, synthesis, and mechanistic considerations
Jensen, David R.,Schultz, Mitchell J.,Mueller, Jaime A.,Sigman, Matthew S.
, p. 3810 - 3813 (2003)
A breath of fresh air: A variety of alcohols are oxidized using 0.5-0.1 mol% of the catalyst, and in some cases the oxidation can simply be carried out open to the air (see scheme). Mechanistic insight into the mechanism is provided by a crystal structure that shows remarkable hydrogen bonds between the coordinated water and acetate ligands and an unprecedented large kinetic isotope effect.
Identification of an ASE2 Mechanism in the Hydrolysis of Cyclic Thioacetals
Ali, Muhammad,Satchell, Derek P. N.
, p. 866 - 867 (1991)
2-Phenyl-2-methyl-1,3-dithiane and its p-methoxy derivative undergo hydrolysis in concentrated aqueous perchloric acid via the ASE2 mechanism rather than via the A1 mechanism.
Ruthenium carbonyl complexes with pyridine-alkoxide ligands: Synthesis, characterization and catalytic application in dehydrogenative oxidation of alcohols
Hao, Zhiqiang,Yan, Xinlong,Liu, Kang,Yue, Xiaohui,Han, Zhangang,Lin, Jin
, p. 15472 - 15478 (2018)
Several new trinuclear ruthenium carbonyl complexes chelated with 6-bromopyridine alcohol ligands, [6-bromopyC(CH2)4O]Ru3(CO)9 (1a), [6-bromopyC(CH2)5O]Ru3(CO)9 (1b), [6-bromopyC(Me)2O]Ru3(CO)9 (1c) and [6-bromopyCMeC6H5O]Ru3(CO)9 (1d), were synthesized by the reaction of Ru3(CO)12 with 6-bromopyC(CH2)4OH (L1H), 6-bromopyC(CH2)5OH (L2H), 6-bromopyC(Me)2OH (L3H) and 6-bromopyCMeC6H5OH (L4H) in refluxing THF, respectively. The free ligands L1H-L4H were synthesized by the nucleophilic reaction of lithium salt (generated from 2,6-dibromopyridine and n-BuLi) with the corresponding ketones. Furthermore, these pyridine-based ligands were characterized by NMR spectroscopy and elemental analyses. All the four ruthenium carbonyl complexes were well characterized by NMR, IR, single-crystal X-ray crystallography, etc. Complexes 1a-1d were found to exhibit high catalytic activities for the dehydrogenative oxidation of secondary alcohols to give their corresponding products in good to excellent yields.
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Kosolapoff
, p. 1651 (1947)
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Rh- and Ru-complex-catalyzed dimerization of arylethynes Rylethynes in aqueous environment
Novak, Petr,Kotora, Martin
, p. 433 - 442 (2009)
Complexes [RhCl(PPh3)3] and [Ru(CHPh)Cl 2(PCy3)2] efficiently catalyzed the dimerization of arylethynes to the corresponding 1,4-substituted enynes in aqueous environment in the presence of sodium dodecyl sulfate. The Rh catalyst exhibited almost exclusive preference for the formation of ￡-isomers, the Ru one exhibits strong preference for the formation of Z-isomers.
Light-driven carbon dioxide reduction coupled with conversion of acetylenic group to ketone by a functional Janus catalyst based on keplerate {Mo132}
Lodh, Joyeeta,Mallick, Apabrita,Roy, Soumyajit
, p. 20844 - 20851 (2018)
Catalysts enabling CO2 reduction coupled with another organic reaction are rare. In this study, we report such a catalyst keplerate {Mo132}, which catalyses photochemical carbon dioxide reduction to formic acid coupled with organic transformation, i.e., hydration of phenylacetylene to acetophenone in visible light. It initially oxidizes water and injects the reducing equivalents for reduction of carbon dioxide at the same time, converting acetylenic group to ketone. Our designed redox Janus catalyst provides an inexpensive pathway to achieve carbon dioxide reduction as well as conversion of phenylacetylene to acetophenone, which is an industrially important precursor.
Highly efficient oxidation of alcohols catalyzed by a porphyrin-inspired manganese complex
Dai, Wen,Lv, Ying,Wang, Lianyue,Shang, Sensen,Chen, Bo,Li, Guosong,Gao, Shuang
, p. 11268 - 11271 (2015)
A novel strategy for catalytic oxidation of a variety of benzylic, allylic, propargylic, and aliphatic alcohols to the corresponding aldehydes or ketones by an in situ formed porphyrin-inspired manganese complex in excellent yields (up to 99%) has been successfully developed.
Pd(II)-Mediated Oxidation of Olefine Using the Transannular Ozonides of 9-tert-Butylanthracenes as an Oxygen Atom Source
Matsuura, Akira,Ito, Yoshikatsu,Matsuura, Teruo
, p. 5002 - 5004 (1985)
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Photophysics of Perylene Diimide Dianions and Their Application in Photoredox Catalysis
Li, Han,Wenger, Oliver S.
supporting information, (2021/12/23)
The two-electron reduced forms of perylene diimides (PDIs) are luminescent closed-shell species whose photochemical properties seem underexplored. Our proof-of-concept study demonstrates that straightforward (single) excitation of PDI dianions with green
Copper-Catalyzed Azide-Alkyne Cycloaddition of Hydrazoic Acid Formed in Situ from Sodium Azide Affords 4-Monosubstituted-1,2,3-Triazoles
Jankovi?, Dominik,Virant, Miha,Gazvoda, Martin
, p. 4018 - 4028 (2022/02/25)
We report a copper-catalyzed cycloaddition of hydrogen azide (hydrazoic acid, HN3) with terminal alkynes to form 4-substituted-1H-1,2,3-triazoles in a sustainable manner. Hydrazoic acid was formed in situ from sodium azide under acidic conditions to react with terminal alkynes in a copper-catalyzed reaction. Using polydentate N-donor chelating ligands and mild organic acids, the reactions were realized to proceed at room temperature under aerobic conditions in a methanol-water mixture and with 5 mol % catalyst loadings to afford 4-substituted-1,2,3-triazoles in high yields. This method is amenable on a wide range of alkyne substrates, including unprotected peptides, showing diverse functional group tolerance. It is applicable for late-stage functionalization synthetic strategies, as demonstrated in the synthesis of the triazole analogue of losartan. The preparation of orthogonally protected azahistidine from Fmoc-l-propargylglycine was realized on a gram scale. The hazardous nature of hydrazoic acid has been diminished as it forms in situ in a reactive species in the copper-catalyzed reaction.
Synthetic method of etoricoxib intermediate 4 - methylsulfonyl acetophenone
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Paragraph 0041-0048; 0052-0058; 0062-0081, (2021/08/25)
The synthesis method comprises the following steps: adding anhydrous 4 - aluminum trichloride to a dichloromethane system; adding acetyl chloride to obtain the reaction solution; and adding the chloride to obtain the reaction solution. Step II: The reaction solution is added dropwise to the reaction solution; and the reaction solution is added dropwise to the reaction solution. The aqueous phase is extracted with dichloromethane, the organic phase is combined, and the combined organic phases are washed with 10% sodium hydrogen carbonate aqueous solution. Step IV: The organic phase after washing is evaporated to dryness, n-heptane is added, the crystals are washed and dried to obtain the acetyl benzyl thioether. The method comprises the following steps: adding the acetoxymethylsulfide obtained in the step to the acetone system, further reacting to obtain 4 - methylsulfonyl acetophenone. Or to the acetic acid system, the obtained acetoxymethylsulfide is added, and the mixture is stirred and dissolved to obtain the reaction mixture. A further reaction gave 4 - methylsulfonylacetophenone. It reduces the energy consumption, and the reaction is more stable, and the benefit is high.
