108-43-0Relevant articles and documents
Electrocatalytic reduction of ROOH by iron porphyrins
Collman, James P.,Kaplun, Marina,Sunderland, Christopher J.,Boulatov, Roman
, p. 11166 - 11167 (2004)
Electrocatalytic reduction of a series of chemical oxidants of different power (tert-butyl hydroperoxide, potassium peroxomonosulfate, peracetic acid, and m-chloroperbenzoic acid) at iron-porphyrin-modified graphite electrodes is studied in buffered aqueous solutions by rotating disk and ring-disk voltammetry. Both ferric and ferrous porphyrins are catalytically active. Turnover of ferric catalysts is slower than that of the ferrous analogues and involves competing catalytic reduction and disproportionation. The kinetic data are consistent with reactant binding being the rate-determining step in catalysis by Fe(III). In catalysis by Fe(II), the turnover is controlled by the first electron transfer. The covalently linked proximal imidazole ligand is found to be crucial for achieving the Fe(III) catalysis. Copyright
The interaction of ozone with chlorobenzene
Vysokikh,Yagodovskaya,Savilov,Lunin
, p. 878 - 882 (2007)
The reaction of ozone with chlorobenzene was studied over the temperature range 77-305 K. Ozone was found to oxidize chlorobenzene starting with 77 K to produce a complex mixture of ozonides and peroxides of various compositions. The products of the reaction between chlorobenzene and ozone formed over the temperature range 77-305 K were analyzed by IR Fourier transform spectroscopy. Nauka/Interperiodica 2007.
Benzene Hydroxylation by Bioinspired Copper(II) Complexes: Coordination Geometry versus Reactivity
Anandababu, Karunanithi,Mayilmurugan, Ramasamy,Muthuramalingam, Sethuraman,Velusamy, Marappan
, p. 5918 - 5928 (2020)
A series of bioinspired copper(II) complexes of N4-tripodal and sterically crowded diazepane-based ligands have been investigated as catalysts for functionalization of the aromatic C-H bond. The tripodal-ligand-based complexes exhibited distorted trigonal-bipyramidal (TBP) geometry (τ, 0.70) around the copper(II) center; however, diazepane-ligand-based complexes adopted square-pyramidal (SP) geometry (τ, 0.037). The Cu-NPy bonds (2.003-2.096 ?) are almost identical and shorter than Cu-Namine bonds (2.01-2.148 ?). Also, their Cu-O (Cu-Owater, 1.988 ? Cu-Otriflate, 2.33 ?) bond distances are slightly varied. All of the complexes exhibited Cu2+ → Cu+ redox couples in acetonitrile, where the redox potentials of TBP-based complexes (-0.251 to -0.383 V) are higher than those of SP-based complexes (-0.450 to -0.527 V). The d-d bands around 582-757 nm and axial patterns of electron paramagnetic resonance spectra [g∥, 2.200-2.251; A∥, (146-166) × 10-4 cm-1] of the complexes suggest the existence of five-coordination geometry. The bonding parameters showed K∥ > K∥ for all complexes, corresponding to out-of-plane πbonding. The complexes catalyzed direct hydroxylation of benzene using 30% H2O2 and afforded phenol exclusively. The complexes with TBP geometry exhibited the highest amount of phenol formation (37%) with selectivity (98%) superior to that of diazepane-based complexes (29%), which preferred to adopt SP-based geometry. Hydroxylation of benzene likely proceeded via a CuII-OOH key intermediate, and its formation has been established by electrospray ionization mass spectrometry, vibrational, and electronic spectra. Their formation constants have been calculated as (2.54-11.85) × 10-2 s-1 from the appearance of an O (π?σ) → Cu ligand-to-metal charge-transfer transition around 370-390 nm. The kinetic isotope effect (KIE) experiments showed values of 0.97-1.12 for all complexes, which further supports the crucial role of Cu-OOH in catalysis. The 18O-labeling studies using H218O2 showed a 92% incorporation of 18O into phenol, which confirms H2O2 as the key oxygen supplier. Overall, the coordination geometry of the complexes strongly influenced the catalytic efficiencies. The geometry of one of the CuII-OOH intermediates has been optimized by the density functional theory method, and its calculated electronic and vibrational spectra are almost similar to the experimentally observed values.
Catalysis by Amberlite IR-120 resin: A rapid and green method for the synthesis of phenols from arylboronic acids under metal, ligand, and base-free conditions
Mulakayala, Naveen,Ismail,Kumar, Kottur Mohan,Rapolu, Rajesh Kumar,Kandagatla, Bhaskar,Rao, Pallavi,Oruganti, Srinivas,Pal, Manojit
, p. 6004 - 6007,4 (2012)
A clean process has been developed for the ipso-hydroxylation of aryl and heteroaryl boronic acids to the corresponding phenols using commercially available and recyclable Amberlite IR-120 resin and aqueous hydrogen peroxide as an oxidizing agent. The ion-exchange sulfonic acid resin catalyst could be readily recycled by filtration and directly reused at least four times without any significant loss of activity.
Aryl phenol compound as well as synthesis method and application thereof
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Paragraph 0071-0074, (2021/05/12)
The invention discloses a synthesis method of an aryl phenol compound shown as a formula (3). All systems are carried out in an air or nitrogen atmosphere, and visible light is utilized to excite a photosensitizer for catalyzation. In a reaction solvent, ArNR1R2 as shown in a formula (1) and water as shown in a formula (2) are used as reaction raw materials and react under the auxiliary action of acid to obtain the aryl phenol compound as shown in a formula (3). The ArNR1R2 in the formula (1) can be primary amine and tertiary amine, can also be steroid and amino acid derivatives, and can also be drugs or derivatives of propofol, paracetamol, ibuprofen, oxaprozin, indomethacin and the like. The synthesis method has the advantages of cheap and easily available raw materials, simple reaction operation, mild reaction conditions, high reaction yield and good compatibility of substrate functional groups. The fluid reaction not only can realize amplification of basic chemicals, but also can realize amplification of fine chemicals, such as synthesis of drugs propofol and paracetamol. The invention has wide application prospect and use value.
Highly recyclable Ti0.97Ni0.03O1.97catalyst coated on cordierite monolith for efficient transformation of arylboronic acids to phenols and reduction of 4-nitrophenol
Hegde, M. S.,Prasanna,Usha, K. M.
supporting information, p. 14223 - 14234 (2021/10/25)
A stable Ni2+substituted TiO2catalyst (Ti0.97Ni0.03O1.97) has been synthesized by a solution combustion method with an average crystallite size of 7.5 nm. Ti1?xNixO2?x(x= 0.01-0.06) crystallizes in the TiO2anatase structure with Ni2+substituted in Ti4+ion sites and Ni taking a nearly square planar geometry. This catalyst is found to be highly active in the transformation of diverse arylboronic acids to the corresponding phenols. The catalyst coated cordierite monolith can even be recycled for up to 20 cycles with a cumulative TOF of 1.8 × 105h?1. In scale-up reactions, various phenols are synthesized by employing a single cordierite monolith. It also shows high performance in the reduction of 4-nitrophenol.
Catalyst-free rapid conversion of arylboronic acids to phenols under green condition
Dong, Zhenhua,Liu, Mengmeng,Pan, Hongguo
, (2021/09/06)
A catalyst-free and solvent-free method for the oxidative hydroxylation of aryl boronic acids to corresponding phenols with hydrogen peroxide as the oxidizing agent was developed. The reactions could be performed under green condition at room temperature within very short reaction time. 99% yield of phenol could be achieved in only 1 min. A series of different arenes substituted aryl boronic acids were further carried out in the hydroxylation reaction with excellent yield. It was worth nothing that the reaction could completed within 1 min in all cases in the presence of ethanol as co-solvent.
Coordination Polymers as a Functional Material for the Selective Molecular Recognition of Nitroaromatics and ipso-Hydroxylation of Arylboronic Acids
Bhasin, K. K.,Husain, Ahmad,Kumar, Girijesh,Rani, Pooja
, (2021/12/06)
We report the synthesis and structural characterization of two coordination polymers (CPs), namely; [{Zn(L)(DMF)4} ? 2BF4]α (1) and [{Cd(L)2(Cl)2} ? 2H2O]α (2) (where L=N2,N6-di(pyridin-4-yl)naphthalene-2,6-dicarboxamide). Crystal packing of 1 reveals the existence of channels running along the b- and c-axis filled by the ligated DMF and lattice anions, respectively. Whereas, crystal packing of 2 reveals that the metallacycles of each 1D chain are intercalating into the groove of adjacent metallacycles resulting in the stacking of 1D loop-chains to form a sheet-like architecture. In addition, both 1 and 2 were exploited as multifunctional materials for the detection of nitroaromatic compounds (NACs) as well as a catalyst in the ipso-hydroxylation of aryl/heteroarylboronic acids. Remarkably, 1 and 2 showed high fluorescence stability in an aqueous medium and displayed a maximum 88% and 97% quenching efficiency for 4-NPH, respectively among all the investigated NACs. The mechanistic investigation of NACs recognition suggested that the fluorescence quenching occurred via electron as well as energy transfer process. Furthermore, the ipso-hydroxylation of aryl/heteroarylboronic acids in presence of 1 and 2 gave up to 99% desired product yield within 15 min in our established protocol. In both cases, 1 and 2 are recyclable upto five cycles without any significant loss in their efficiency.
Highly efficient, recyclable and alternative method of synthesizing phenols from phenylboronic acids using non-endangered metal: Samarium oxide
Yusoff, Hanis Mohd,Bala Chandran, Prasana Devi,Sayuti, Fatin Amira Binti,Kan, Su-Yin,Mohd Radzi, Siti Aisha,Yong, Fu-Siong Julius,Lee, Oon Jew,Chia, Poh Wai
, (2021/06/25)
Oxidation of phenylboronic acid to phenol is one of the important industrial processes and it is generally employed in the plastic, explosive and drug manufacturing industries. Over the past decades, numerous efficient methods have been described for the generation of phenols from phenylboronic acids in the presence of oxidant. However, these methods suffered from various limitations, including the use of expensive, toxic reagents and sophisticated protocol to synthesise the phenols. Additionally, some of these reported literatures employed endangered metals, in which mankind is facing the risk of limited supply of these elements in 20 years’ time from now. As such, a viable alternative and green method for achieving organic synthesis is highly sought after by the chemists of today. Herein, we report for the first time a facile, efficient and alternative method in the preparation of phenols from phenylboronic acids using non-endangered metal as catalyst. In all cases, all phenols were afforded in satisfactory yields (81–96%) by employing column-free method. In the recyclability study, the Sm2O3 catalyst was found to possess good catalytic performance, even after being reused for five consecutive times (96–91%). In addition, SEM result revealed that the morphology of the recycled Sm2O3 catalyst was well preserved after five successive uses, which indicate no observable changes occurred in the recovered catalysts. As a final note, the current method is anticipated to be useful for industries manufacturing chemical intermediates as it provides an alternative method of catalysis by using a non-endangered metal in organic transformations.
An efficient Ti0.95Cu0.05O1.95 catalyst for ipso – hydroxylation of arylboronic acid and reduction of 4-nitrophenol
Bhat, Shrikanth K,Dasappa, Jagadeesh Prasad,Hegde, M. S.,Prasanna
, (2021/08/12)
A stable, active and selective Ti0.95Cu0.05O1.95 catalyst, crystallized in anatase TiO2 structure with 5% Cu2+ ions substituted for Ti4+ ions with 5% oxide ion vacancy has been synthesized by solution combustion method. The catalyst was coated over a cordierite monolith (Mg2Al4Si5O18) by solution combustion method. By the first principle density functional theory (DFT) calculations, 48 atoms bulk structure has been optimized and density of states (DOS) has been calculated. Ti – O bond distribution in Ti0.95Cu0.05O1.95 has been compared with pure TiO2. Bond distribution analysis has shown longer Cu – O and Ti – O bonds compared to those in CuO and TiO2 creating Cu2+ and oxide ion vacancy as electrophilic and nucleophilic active sites, respectively. This catalyst was found to be very active for ipso – hydroxylation of arylboronic acid and 4-nitrophenol reduction reactions at room temperature. Catalyst coated cordierite monolith was used in the recycling process of the reaction for 20 cycles and cumulative turnover frequency was found to be 184,840 h?1. Ti0.95Cu0.05O1.95 catalyst coated on cordierite monolith enhanced the rate of the reaction compared to powder catalyst and made the handling and recycling of the catalyst very easy. Graphic abstract: [Figure not available: see fulltext.]
