104-88-1Relevant articles and documents
Catalytic oxidation of benzyl alcohols by new Cu(II) complexes of 1,3-oxazolidine based ligand obtained from a solvent free reaction
Bikas, Rahman,Ajormal, Fatemeh,Emami, Marzieh,Noshiranzadeh, Nader,Kozakiewicz, Anna
, p. 77 - 87 (2018)
A new 1,3-oxazolidine based ligand, (2-pyridin-2-yl-1,3-oxazolidine-4,4-diyl)dimethanol (H3L), has been synthesized from the reaction of 2-amino-2-(hydroxymethyl)-1,3-propanediol and 2-pyridinecarboxaldehyde at 110 °C. Two mononuclear Cu(II) complexes, [Cu(H3L)Cl2]·CH3OH (1) and [Cu(H3L)2]·2Cl (2), have been synthesized with a similar procedure by the reaction of H3L and CuCl2·H2O in 1:1 and 2:1 M ratios in methanol. The ligand and complexes have been characterized by elemental analysis and spectroscopic methods. The structure of complexes has been characterized by single-crystal X-ray diffraction analysis which showed the copper ion has a distorted square pyramidal geometry in 1 and distorted octahedral geometry in 2. The 1,3-oxazolidine ligand acts as a neutral tridentate N2O-donor ligand in both 1 and 2. Two chloride anions remain coordinated to Cu(II) ion in complex 1, but they act as counter ions in complex 2. The catalytic activity of these complexes has been investigated in the oxidation of benzyl alcohol by using H2O2 or TBHP as oxidant. The effects of some influential parameters in catalytic reactions like molar ratio of oxidant-to-substrate, temperature, nature of oxidant and solvent have been studied to obtain the optimum condition. Moreover, the effects of chlorine substituent on the phenyl group (ortho-, meta- and para-positions) has also been explored. The results of these studies show that both 1 and 2 catalyze the oxidation of benzyl alcohol derivatives to the corresponding benzaldehydes and a little amount of the related benzoic acids, produced by over oxidation of benzaldehyde, are also detected in the reaction mixtures. The results indicate that the selectivity and the activity of these catalytic systems depend on the reaction conditions and the steric and electronic properties of the reagents.
A new application of N-bromosaccharin as a selective and efficient oxidative reagent for regeneration of carbonyl compounds from oximes
Khazaei, Ardeshir,Manesh, Abbas Amini,Rostami, Amin
, p. 2483 - 2486 (2004)
A new method for the direct conversion of various oximes into aldehydes and, ketones by treatment with N-bromosaccharin is described. N-bromosaccharin can be used for an effective, selective and mild oxidizing agent for the regeneration of carbonyl compounds from oximes in good yield.
A highly efficient heterogeneous copper-catalyzed chlorodeboronation of arylboronic acids leading to chlorinated arenes
He, Wen,Zhang, Rongli,Cai, Mingzhong
, p. 764 - 770 (2017)
A highly efficient heterogeneous copper-catalyzed chlorodeboronation of arylboronic acids with inexpensive N-chlorosuccinimide (NCS) was achieved in MeCN in the presence of 10 mol% of l-proline-functionalized MCM-41-immobilized copper(i) complex [MCM-41-l-proline-CuCl] under mild conditions, yielding a variety of aryl chlorides in excellent yields. This method proved to be tolerant of a broad range of functional groups and particularly useful for the conversion of electron-deficient arylboronic acids to aryl chlorides, a transformation that is inefficient without copper catalysis. This heterogeneous copper catalyst can be recovered by a simple filtration of the reaction solution and recycled for at least 10 times without any decreases in activity.
Aqueous electrosynthesis of carbonyl compounds and the corresponding homoallylic alcohols in a divided cell
Zhang, Li,Zha, Zhenggen,Wang, Zhiyong,Fu, Shengquan
, p. 1426 - 1429 (2010)
An aqueous paired electrosynthesis is studied in a divided cell. On graphite anode Br- was oxidized to Br2 and this generated Br2 oxidized alcohols to the corresponding carbonyl compounds while Sn2+ was reduced
Aerobic oxidation of benzyl- and allylic alcohols under visible light irradiation of a fluorescent lamp in the presence of catalytic iodine
Nakayama, Hiroki,Itoh, Akichika
, p. 1620 - 1621 (2006)
Benzyl alcohols and allylic alcohols were found to be oxidized to the corresponding aldehydes in the presence of a catalytic amount of iodine under irradiation of a fluorescent lamp.
Heterogeneous photocatalytic anaerobic oxidation of alcohols to ketones by Pt-mediated hole oxidation
Sun, Danhui,Li, Peihe,Wang, Xia,Wang, Yingying,Wang, Jinghui,Wang, Yin,Lu, Ye,Duan, Limei,Sarina, Sarina,Zhu, Huaiyong,Liu, Jinghai
, p. 11847 - 11850 (2020)
We report a platinum nanocluster/graphitic carbon nitride (Pt/g-C3N4) composite solid catalyst with a photocatalytic anaerobic oxidation function for highly active and selective transformation of alcohols to ketones. The desirable products were successfully obtained in good to excellent yields from various functionalized alcohols at room temperature, including unactivated alcohols. Mechanistic studies indicated that the reaction could proceed through a Pt-mediated hole oxidation initiating an α-alcohol radical intermediate followed by a two-electron oxidation pathway. The merit of this strategy offers a general approach towards green and sustainable organic synthetic chemistry.
Solid state deprotection of thioacetals and thioketals using 1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane periodate and aluminum chloride
Hajipour, Abdol Reza,Ruoho, Arnold E.
, p. 298 - 303 (2005)
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Magtrieve: A convenient catalyst for the oxidation of alcohols
Few, Chip S.,Williams, Kathryn R.,Wagener, Kenneth B.
, p. 4452 - 4454 (2014)
We find that Magtrieve (CrO2) catalyzes the oxidation of a wide variety of alcohols with periodic acid as the terminal oxidant. Mild conditions, short reaction times, and facile aqueous work-up make this a most attractive method. Olefins are not oxidized under these conditions; thus alcohols react selectively in the presence of alkenes. Conditions have been optimized with respect to catalyst loading, solvent, and co-oxidant; and the scope of the reaction includes primary and secondary benzylic, allylic, and aliphatic alcohols.
Highly practical sodium(i)/azobenzene catalyst system for aerobic oxidation of benzylic alcohols
Liu, Chengkou,Fang, Zheng,Yang, Zhao,Li, Qingwen,Guo, Shiyu,Guo, Kai
, p. 79699 - 79702 (2015)
An economic, environmental and practical aerobic oxidation of benzylic alcohols and hetero aryl alcohols to the corresponding carbonyl compounds with good substrate scope is disclosed for the first time. Good to excellent yields were obtained by employing economic and commercially available sodium bromide and a catalytic amount of azobenzene under metal-free and ligand-free conditions. Moreover, aldehydes and acids, the oxidation products of benzylic 1° alcohols, could be obtained using sodium bromide and sodium hydroxide as the co-catalyst respectively in high yields.
Tsuji-Wacker Oxidation of Terminal Olefins using a Palladium-Carbon Nanotube Nanohybrid
Donck, Simon,Gravel, Edmond,Shah, Nimesh,Jawale, Dhanaji V.,Doris, Eric,Namboothiri, Irishi N. N.
, p. 2318 - 2322 (2015)
Palladium nanoparticles supported on carbon nanotubes were used in the Tsuji-Wacker oxidation. The palladium-based nanohybrid was found to be very active in combination with cuprous chloride for the selective oxidation of terminal olefins into methyl ketones. The co-catalytic system operates under very mild and sustainable conditions (room temperature, atmospheric pressure, low catalyst loading), as opposed to previously reported catalysts, and can be recycled without any loss in activity. Give it a whack: Palladium nanoparticles supported on carbon nanotubes are used in combination with cuprous chloride for the selective Tsuji-Wacker oxidation of terminal olefins into methyl ketones. The co-catalytic system operates under very mild and sustainable conditions and can be recycled without any loss in activity.
Reactions of OH and SO4.- with Some Halobenzenes and Halotoluenes: A Radiation Chemical Study
Merga, Getahun,Rao, B. S. M.,Mohan, H.,Mittal, J. P.
, p. 9158 - 9164 (1994)
The optical absorption and kinetic characteristics of the transients formed in the reactions of OH and SO4.- with bromobenzene, ortho and meta-isomers of chloro- and bromobenzenes, and monobromotoluenes have been studied by pulse radiolysis technique.The rates for OH reaction are generally higher (k = (1.7-4.4)X109 M-1s-1) than those found for the SO4.- reaction (k = (0.4-2.3)x109 M-1s-1). ρ+ values of -0.4 for OH and -1.2 for SO4.- reactions were obtained from the Hammett analysis.The formation of substituted hydroxycyclohexadienyl radicals (λmax = 315-330 nm) is the major reaction channel, and the phenoxyl type radical (λ >/=400 nm) formation is an additional minor process in the SO4.- reaction.Abstraction of H by SO4.- from the -CH3 group is only significant with the para-isomers of bromo- and chlorotoluenes.This result is in accord with the observed yields (70 percent of SO4.-) of the products resulting from the oxidation of the 4-chlorobenzyl radical in the presence of K3Fe(CN)6 under steady-state conditions.The total yields of the phenolic products accounting for >90 percent of OH and SO4.- suggest that the attack at the ipso positions is considerably small.The rate constants for OH reactions relative to benzene at positions 3 and 6 of 2-chlorotoluene and positions 2 and 3 of 4-chlorotoluene are between 1.18 and 1.39, indicating that the directing effects of -CH3 and -Cl groups are comparable.This is also reflected in the additive effects of activation of the ortho and para-positions and deactivation of meta-positions by these substituents in 3-chlorotoluene.
Oxidation of benzylic alcohols with butyltriphenylphosphonium permanganate under non-aqueous conditions
Hajipour, Abdol Reza,Mallakpour, Shadpour E.,Samimi, Heshmat A.
, p. 3831 - 3838 (2002)
Oxidation of benzylic alcohols with butyltriphenylphosphonium permanganate (BuPh3P+MnO4-) 1 (BTPPPM) in acetonitrile at room temperature is reported. This reagent selectively oxidizes benzylic alcohols in the presence of other oxidizable functional groups.
Magnetic crosslinked copoly(ionic liquid) nanohydrogel supported palladium nanoparticles as efficient catalysts for the selective aerobic oxidation of alcohols
Gholinejad, Mohammad,Afrasi, Mahmoud,Nikfarjam, Nasser,Nájera, Carmen
, p. 185 - 195 (2018)
Nowadays it is still a great sustainable processes challenge to produce efficient, selective and easy magnetic recovery and recycling catalysts for oxidation of alcohols using air as the oxidant. In this work, a new magnetic nanohydrogel comprising [DABCO-allyl][Br] ionic liquid, allyl alcohol and N,N’-methylenebis(acrylamide) is used for stabilization of small and highly uniform palladium nanoparticles of 3–4 nm size MXCPILNHG@Pd. This material has been characterized by Fourier-transform infrared spectroscopy (FTIR), atomic adsorption spectroscopy (AAS), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), SEM-Map, energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectra (XPS), vibrating-sample magnetometer (VSM) and dynamic light scattering (DLS). According to optimization of cross-linking degree and ratio of DABCO-IL, MXCPILNHG-2@Pd is found as a highly selective catalyst in oxidations of primary alcohols to the corresponding aldehydes in toluene and to acids in water. Furthermore, secondary alcohols were reacted efficiently to the corresponding ketones in both toluene and water. Catalyst is magnetically recovered and recycled for several times in both toluene and water and the reused catalysts are characterized by TEM and XPS.
Symmetric quaternary phosphonium cation and perchlorate/chlorate anions: Crystal structure, Database study and Hirshfeld surface analysis
Salmasi,Salimi,Gholizadeh,Rahmani,Garrison
, p. 549 - 557 (2019)
Two new quaternary phosphonium salts of 1,2-ethandiylbis (triphenylphosphonium) Diperchlorate (I), 1,2-ethandiylbis (triphenylphosphonium) Dichlorate (II) were prepared and used for oxidation of different benzylic alcohols to afford their corresponding ca
SBA-15 Supported 1-Methyl-2-azaadamanane N-Oxyl (1-Me-AZADO) as Recyclable Catalyst for Oxidation of Alcohol
Tian, Yangwu,Guo, Xiaqun,Li, Meichao,Li, Chunmei,Hu, Xinquan,Jin, Liqun,Sun, Nan,Hu, Baoxiang,Shen, Zhenlu
, p. 3928 - 3932 (2021)
Herein, we designed and synthesized an SBA-15 supported 1-methyl-2-azaadamanane N-oxyl (1-Me-AZADO) and investigated its catalytic performance for selective oxidation of alcohols under Anelli's conditions. The first example of immobilization of 1-Me-AZADO was very important to advance the oxgenation effectively because this supported N-oxyl has excellent catalytic activity for oxidation of alcohols to carbonyl compounds, and more importantly, it can be conveniently recovered and reused at least 6 times without significant effect on its catalytic efficiency.
Mannich base Cu(II) complexes as biomimetic oxidative catalyst
Kundu, Bidyut Kumar,Ranjan, Rishi,Mukherjee, Attreyee,Mobin, Shaikh M.,Mukhopadhyay, Suman
, p. 164 - 173 (2019)
Galactose Oxidase (GOase) and catechol oxidase (COase) are the metalloenzymes of copper having monomeric and dimeric sites of coordination, respectively. This paper summarizes the results of our studies on the structural, spectral and catalytic properties of new mononuclear copper (II) complexes [CuL(OAc)] (1), and [CuL2] (2), (HL = 2,4?dichloro?6?{[(2′?dimethyl?aminoethyl)methylamino]methyl}?phenol) which can mimic the functionalities of the metalloenzymes GOase and COase. The structure of the compounds has been elucidated by X-ray crystallography and the mimicked Cu(II) catalysts were further characterized by EPR. These mimicked models were used for GOase and COase catalysis. The GOase catalytic results were identified by GC–MS and, analyzed by HPLC at room temperature. The conversion of benzyl alcohol to benzaldehyde were significant in presence of a strong base, Bu4NOMe in comparison to the neutral medium. Apart from that, despite of being monomeric in nature, both the homogeneous catalysts are very prone to participate in COase mimicking oxidation reaction. Nevertheless, during COase catalysis, complex 1 was found to convert 3,5?ditertarybutyl catechol (3,5-DTBC) to 3,5?ditertarybutyl quinone (3,5-DTBQ) having greater rate constant, kcat or turn over number (TON) value over complex 2. The generation of reactive intermediates during COase catalysis were accounted by electrospray ionization mass spectrometry (ESI-MS). Through mechanistic approach, we found that H2O2 is the byproduct for both the GOase and COase catalysis, thus, confirming the generation of reactive oxygen species during catalysis. Notably, complex 1 having mono-ligand coordinating atmosphere has superior catalytic activity for both cases in comparison to complex 2, that is having di-ligand environment.
A new layered metal-organic framework as a promising heterogeneous catalyst for olefin epoxidation reactions
Zhang, Jingming,Biradar, Ankush V.,Pramanik, Sanhita,Emge, Thomas J.,Asefa, Tewodros,Li, Jing
, p. 6541 - 6543 (2012)
A new layered MOF material [Co(Hoba)2·2H2O] (1) (H2oba = 4,4′-oxybis(benzoic acid)) has been synthesized and used as a highly recyclable heterogeneous catalyst for olefin epoxidation reactions. Both high conversion (96%) and high selectivity of epoxide products (96%) are achieved.
A CONVENIENT SYNTHESIS OF EPOXIDES FROM OLEFINS USING MOLECULAR OXYGEN IN THE ABSENCE OF METAL CATALYSTS
Kaneda, Kiyotomi,Haruna, Shigeru,Imanaka, Toshinobu,Hamamoto, Masatoshi,Nishiyama, Yutaka,Ishii, Yasutaka
, p. 6827 - 6830 (1992)
The system consisting of molecular oxygen and aldehydes (e.g., isobutyraldehyde and pivalaldehyde) oxidizes various olefins to give epoxides in high yields at 40 deg C for 3-6 h.Key Words: Epoxidation, Olefin, Molecular oxygen, Aldehyde
Mixed Monosilyl Acetals and Catalyst-Dependent Chemoselective Mukaiyama Aldol Reactions
Kim, Sun Min,Yang, Hye Sung,Eum, Heesung,Ha, Hyun-Joon,Yang, Jung Woon
, p. 16432 - 16437 (2017)
We report a direct, simple, and straightforward approach for the construction of a mixed monosilyl acetal as a new and synthetically valuable functional group by mixing an aldehyde, sodium tert-butoxide, and trimethylsilyl azide. We also demonstrate a catalyst-dependent chemoselective reaction between mixed monosilyl acetals and silyl ketene acetals through Mukaiyama aldol reactions to give different structures of O-protected β-hydroxy esters in excellent yields with high chemoselectivities. This study provided the existence of an oxonium ion intermediate and of its kinetically controlled reaction with the pre-equilibrated silyl enol ether obtained from (E)- and (Z)-isomerization.
Design and synthesis of hybrid solids based on the tetravanadate core toward improved catalytic properties
Niu, Yan-Hong,Yang, Song,Li, Ji-Kun,Xu, Yan-Qing,Hu, Chang-Wen
, p. 649 - 654 (2016)
Five inorganic-organic hybrid vanadates based on tetravanadate cores, transition metals and N-donor ligands have been designed and synthesized under hydrothermal conditions, namely, [Zn(eIM)3]2V4O12 (1), [Zn(pIM)3]2V4O12·H2O (2), [Zn(ipIM)3]2V4O12 (3), [Co(eIM)3]2V4O12·H2O (4), [Cu(eIM)2(H2O)]2V4O12 (5) (eIM = 1-ethylimidazole, pIM = 1-propylimidazole, ipIM = isopropylimidazole). All compounds were fully characterized by single-crystal XRD, powder XRD, elemental analysis, TGA, and FT-IR spectroscopy. The hybrid zinc vanadates (1-3) and cobalt vanadate (4) exhibit interesting 2D folded structures and the hybrid copper vanadate (5) presents a 1D chain configuration. All compounds can catalyze olefin epoxidation reactions when using TBHP (TBHP = tert-butyl hydroperoxide) as an oxidant in acetonitrile. The introduction of transition metal ions into tetravanadate cores not only improved the catalytic activity but also fulfilled the heterogeneous catalytic behavior. 1-5 all exhibit extraordinary efficiency in converting olefins to the corresponding epoxides with high conversion and selectivity (particularly, conv. up to 97.1%, sele. up to 100% for 1). Leaching test was also carried out to prove the heterogeneous behavior.
Poly(9,9′-spirobifluorene-manganese porphyrin): A new catalytic material for oxidation of alkenes by iodobenzene diacetate and iodosylbenzene
Poriel, Cyril,Ferrand, Yann,Le Maux, Paul,Raul-Berthelot, Joelle,Simonneaux, Gerard
, p. 1104 - 1105 (2003)
Anodic oxidation of tetraspirobifluorene-manganese porphyrin lead to the coating of the working electrode by insoluble electroactive poly(9,9′-spirobifluorene-manganese porphyrin) films for which electrochemical behaviour and physicochemical properties are described; these polymeric materials are able to catalyze the heterogeneous epoxidation of styrene with iodobenzene diacetate and iodosylbenzene.
Crystal structure and solid state computational (DFT/Hirshfeld surface) study for probing a new efficient and recyclable oxidation reagent, 1,2-ethandiylbis(triphenylphosphonium) peroxodisulfate dihydrate
Salmasi,Salimi,Gholizadeh,Abolghasempour,Garrison, Jered C.
, p. 1380 - 1387 (2016)
A new, efficient and recyclable reagent, 1,2-Ethandiylbis(triphenylphosphonium) peroxodisulfate dihydrate, for the oxidation of benzylic alcohols has been synthesized and characterized by IR, NMR spectroscopy, and single crystal X-ray crystallography. Usi
Halogen/lithium exchange in hydrocarbon media; Basic and continuous reactor studies
Slocum,Kusmic, Damir,Raber, Jeffrey C.,Reinscheld, Thomas K.,Whitley, Paul E.
, p. 4793 - 4796 (2010)
The halogen/lithium (X/Li) exchange's usefulness is challenged by the extreme conditions employed during the conversion of a bromo or an iodo substituent to an organolithium intermediate. Our preliminary disclosure reveals that simple X/Li exchanges can be accomplished at ambient temperature and in doped hydrocarbon media using n-BuLi. Use of a continuous reactor featuring brief reaction times (≤1 s) and large product throughputs further facilitates the production of a product resulting from a sequential X/Li exchange and nucleophilic addition.
Cu(II) Schiff base complex supported on Fe3O4 nanoparticles as an efficient nanocatalyst for the selective aerobic oxidation of alcohols
Aghajani, Milad,Monadi, Niaz
, (2018)
Herein, we have prepared a new Cu(II) Schiff base complex supported onto the surface of modified Fe3O4 nanoparticles as highly stable, heterogeneous and magnetically recyclable nanocatalyst for the selective aerobic oxidation of different alcohols. The structure, morphology, chemical composition and magnetic property of the nanocatalyst and its precursors were characterized using FT-IR, TGA, AAS, ICP-AES, XRD, SEM, EDS, VSM and N2 adsorption–desorption analyses. Characterization results exhibited the uniform spherical morphology for nanocatalyst and its precursors. A promising eco-friendly method with short reaction time and high conversion and selectivity for oxidation of various primary and secondary alcohols under O2 atmosphere condition was achieved. The synthesized nanocatalyst could be recovered easily by applying an external magnetic field and reused for least eight subsequent reaction cycles with only negligible deterioration in catalytic performance.
Direct aza-Diels-Alder reaction in water catalyzed by layered α-zirconium hydrogen phosphate and sodium dodecyl sulfate
Costantino, Umberto,Fringuelli, Francesco,Orru, Mara,Nocchetti, Morena,Piermatti, Oriana,Pizzo, Ferdinando
, p. 1214 - 1220 (2009)
The direct aza-Diels-Alder reaction between 2-cyclohexen-1-one (1) and benzaldimines 2 in water is reported for the first time. The reaction occurs at 30°C, is catalyzed by layered α-zirconium hydrogen phosphate (α-ZrP) and requires the presence of sodium dodecyl sulfate (SDS). The reaction yield is excellent, the reaction is faster and the exo diastereo-selectivity is higher than when organic solvent is used. The one-pot, three-component version of the reaction and the recycling of both the catalyst and the aqueous mother liquor in toto (water, α-ZrP and SDS) have also been investigated. Wiley-VCH Verlag GmbH & Co. KGaA, 2009.
Functionalized-1,3,4-oxadiazole ligands for the ruthenium-catalyzed Lemieux-Johnson type oxidation of olefins and alkynes in water
Hkiri, Shaima,Touil, Soufiane,Samarat, Ali,Sémeril, David
, (2021/11/30)
Three arene-ruthenium(II) complexes bearing alkyloxy(5-phenyl-1,3,4-oxadiazol-2-ylamino)(4-trifluoromethylphenyl)methyl ligands were quantitatively obtained through the reaction of (E)-1-(4-trifluoromethylphenyl)-N-(5-phenyl-1,3,4-oxadiazol-2-yl)-methanimine with the ruthenium precursor [RuCl2(η6-p-cymene)]2 in a mixture of the corresponding alcohol and CH2Cl2 at 50 °C. The obtained complexes were fully characterized by elemental analysis, infrared, NMR and mass spectrometry. Solid-state structures confirmed the coordination of the 1,3,4-oxadiazole moiety to the ruthenium center via their electronically enriched nitrogen atom at position 3 in the aromatic ring. These complexes were evaluated as precatalysts in the Lemieux-Johnson type oxidative cleavage of olefins and alkynes in water at room temperature with NaIO4 as oxidizing agent. Good to full conversions of olefins into the corresponding aldehydes were measured, but low catalytic activity was observed in the case of alkynes. In order to get more insight into the mechanism, three analogue arene-ruthenium complexes were synthesized and tested in the oxidative cleavage of styrene. The latter tests clearly demonstrated the importance of the hemilabile alkyloxy groups, which may form more stable (N,O)-chelate intermediates and increase the efficiency of the cis-dioxo-ruthenium(VI) catalyst.
Controlled reduction of activated primary and secondary amides into aldehydes with diisobutylaluminum hydride
Azeez, Sadaf,Kandasamy, Jeyakumar,Sabiah, Shahulhameed,Sureshbabu, Popuri
supporting information, p. 2048 - 2053 (2022/03/31)
A practical method is disclosed for the reduction of activated primary and secondary amides into aldehydes using diisobutylaluminum hydride (DIBAL-H) in toluene. A wide range of aryl and alkyl N-Boc, N,N-diBoc and N-tosyl amides were converted into the corresponding aldehydes in good to excellent yields. Reduction susceptible functional groups such as nitro, cyano, alkene and alkyne groups were found to be stable. Broad substrate scope, functional group compatibility and quick conversions are the salient features of this methodology.
Catalytic alcohol oxidation using cationic Schiff base manganeseIII complexes with flexible diamino bridge
Kakavand, Meysam,Mastrorilli, Piero,Mesto, Ernesto,Neshat, Abdollah,Osanlou, Farzane,Schingaro, Emanuela,Todisco, Stefano
, (2020/11/04)
Four Schiff base manganese(III) complexes with derivatives of [(R,R)-N,N’-bis(salicy1idene)-1,2-cyclohexanediaminato)] including substituents on salicylaldehyde such as 3-methoxy, 3,5-di-tert-butyl and 3,5-chloro were synthesized and characterized using a combination of IR, UV–Vis, and HR ESI-MS techniques. The catalytic activity of these complexes was tested in the oxidation of 1-phenylethanol to acetophenone, revealing very good performances for all of the four manganese complexes. The catalytic reactions were carried out in the presence of tert-butyl hydroperoxide (TBHP) as oxidant and imidazole as co-catalyst. Complex Mn-4, bearing electron withdrawing [(R,R)-N,N’-bis(3,5-di-chloro-salicylidene)-1,2-cyclohexanediaminato)] ligand was found to be the most stable of the tested Mn(III) complexes and was selected for the oxidation of several primary and secondary alcohols.