4460-86-0Relevant academic research and scientific papers
Synthesis of new Zn (II) complexes for photo decomposition of organic dye pollutants, industrial wastewater and photo-oxidation of methyl arenes under visible-light
Ahemed, Jakeer,Bhongiri, Yadagiri,Chetti, Prabhakar,Gade, Ramesh,Kore, Ranjith,Pasha, Jakeer,Pola, Someshwar,Rao D, Venkateshwar
, (2021/07/28)
Synthesis of new Schiff's base Zn-complexes for photo-oxidation of methyl arenes and xylenes are reported under visible light irradiation conditions. All the synthesized new ligands and Zn-complexes are thoroughly characterized with various spectral analyses and confirmed as 1:1 ratio of Zn and ligand with distorted octahedral structure. The bandgap energies of the ligands are higher than its Zn-complexes. These synthesized new Zn(II) complexes are used for the photo-fragmentation of organic dye pollutants, photodegradation of food industrial wastewater and oxidation of methyl arenes which are converted into its respective aldehydes with moderate yields under visible light irradiation. The photooxidation reaction dependency on the intensity of the visible light was also studied. With the increase in the dosage of photocatalyst, the methyl groups are oxidized to get aldehydes and mono acid products, which are also identified from LC-MS data. Finally, [Zn(PPMHT)Cl] is with better efficiency than [Zn(PTHMT)Cl] and [Zn(MIMHPT)Cl] for oxidation of methyl arenes is reported under visible-light-driven conditions.
A metal-free heterogeneous photocatalyst for the selective oxidative cleavage of CC bonds in aryl olefins: via harvesting direct solar energy
Das, Shoubhik,Hatami, Nareh,Jooss, Christian,Lange, Niklas Simon,Ronge, Emanuel,Schilling, Waldemar,Zhang, Yu
supporting information, p. 4516 - 4522 (2020/08/10)
Selective cleavage of CC bonds is highly important for the synthesis of carbonyl containing fine chemicals and pharmaceuticals. Novel methodologies such as ozonolysis reactions, Lemieux-Johnson oxidation reaction etc. already exist. Parallel to these, catalytic methods using homogeneous catalysts also have been discovered. Considering the various advantages of heterogeneous catalysts such as recyclability and stability, couple of transition metal-based heterogeneous catalysts have been applied for this reaction. However, the pharmaceutical industries prefer to use metal-free catalysts (especially transition metal-free) to avoid further leaching in the final products. This is for sure a big challenge to an organic chemist and to the pharmaceutical industries. To make this feasible, a mild and efficient protocol has been developed using polymeric carbon nitrides (PCN) as metal-free heterogeneous photocatalysts to convert various olefins into the corresponding carbonyls. Later, this catalyst has been applied in the gram scale synthesis of pharmaceutical drugs using direct solar energy. Detailed mechanistic studies revealed the actual role of oxygen, the catalyst, and the light source.
Monodentate Transient Directing Group Enabled Pd-Catalyzed Ortho-C-H Methoxylation and Chlorination of Benzaldehydes
Li, Feng,Zhou, Yirong,Yang, Heng,Wang, Ziqi,Yu, Qinqin,Zhang, Fang-Lin
supporting information, p. 3692 - 3695 (2019/05/24)
We report Pd-catalyzed ortho-C-H methoxylation and chlorination of benzaldehydes by employing monodentate transient directing groups (TDGs) as an alternative strategy to bidentate TDGs. More importantly, a single crystal of benzaldehyde imine ortho-cyclopalladium intermediate was successfully obtained, and its structure was unambiguously determined by X-ray diffraction, which clearly showed that it was a binuclear palladium species bridged by a pyridone ligand. The utility of this approach was further demonstrated through the synthesis of key intermediates of natural products and drugs.
Electrophilic Aromatic Formylation with Difluoro(phenylsulfanyl) methane
Betterley, Nolan M.,Kongsriprapan, Sopanat,Chaturonrutsamee, Suppisak,Deelertpaiboon, Pramchai,Surawatanawong, Panida,Pohmakotr, Manat,Soorukram, Darunee,Reutrakul, Vichai,Kuhakarn, Chutima
, p. 2033 - 2040 (2018/03/21)
Difluoro(phenylsulfanyl)methane (PhSCF 2 H) was found to undergo a reaction with aromatic compounds mediated by SnCl 4, through a thionium intermediate characterized by NMR and TD-DFT analyses, leading to the formation of a mixture of S, S ′-diphenyl dithioacetal and aromatic aldehyde which, after oxidative hydrolysis, provides the aromatic aldehyde in good to excellent yields. The salient feature of the present work is the reaction of activated aromatic compounds containing a deactivating ester functional group, leading to the formylated products in good yields.
Enantioselective Total Synthesis and Assignment of the Absolute Configuration of the Meroterpenoid (+)-Taondiol
Dethe, Dattatraya H.,Mahapatra, Samarpita,Sau, Susanta Kumar
supporting information, p. 2766 - 2769 (2018/05/22)
The first enantioselective total synthesis of (+)-taondiol, a pentacyclic marine meroterpenoid, has been achieved, which in addition to confirming the structure also established the absolute configuration of the natural product. The notable points in the synthetic route are synthesis of a highly functionalized tricyclic diterpenoid moiety starting from an enantiopure Wieland-Miescher ketone derivative in concise manner via Robinson-type annulation and an elegant hydrogen atom transfer olefin reduction followed by Lewis acid-catalyzed Friedel-Crafts reaction for one-pot C-C and C-O bond formations resulting in construction of the pentacyclic meroterpenoid skeleton.
Synthesis method of pharmaceutical intermediate 2,4,5-trimethoxybenzoic acid
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Paragraph 0008; 0019-0022, (2018/09/08)
The invention discloses a synthesis method of a pharmaceutical intermediate 2,4,5-trimethoxybenzoic acid. The synthesis method takes 1,2,4-trimethoxybenzene, DMF (Dimethyl Formamide), phosphoryl chloride, 2,4,5-trimethoxybenzaldehyde, silver nitrate, acetonitrile, hydrogen peroxide, zirconium oxide and MCM-41 as main raw materials, and MCM-41 zeolite powder is subjected to short-chain modificationby adopting tetraethyl orthosilicate TEOS; ultrasonic treatment is carried out on a mixed alkali solution and metal ion frameworks of nickel nitrate and aluminum nitrate are used for replacing to form a unique space three-dimensional framework structure with catalytic activity. According to the synthesis method disclosed by the invention, the disadvantages that products are complicated, the products are difficultly completely purified and the like, caused by drastic oxidization reaction of traditional benzaldehyde, are overcome by an intermediate catalyst, and the intermediate catalyst has anexcellent catalysis effect on synthesis reaction of the 2,4,5-trimethoxybenzoic acid.
Toward the total synthesis of citreamicin η: Synthesis of the pentacyclic core and GAB-ring annelation model studies
Blumberg, Shawn,Martin, Stephen F.
, p. 4981 - 4993 (2018/05/23)
A short 11-step synthesis of the pentacyclic core of the polycyclic xanthone antibiotic citreamicin η has been completed. Although the basic approach was inspired by our previous explorations of polycyclic xanthone chemistry, the present report features some new insights into the Moore rearrangement and offers some improvements to our original methodology that include additions of aryllithiums to squarate esters, additions of cerium acetylides to hindered ketones utilizing PDA as an internal indicator, and the use of cyclic di-tert-butylsilyl (DTBS) ethers to protect electron-rich benzyl alcohols toward ionization under acidic conditions. We also developed an improved protocol for selective o-bromination of phenols utilizing N-bromosuccinimide (NBS) and tetramethylguanidine (TMG) that promises to be generally useful. Finally, we developed a modular approach for the synthesis of isoquinolones and dihydro-5H-oxazolo[3,2-b]isoquinoline-2,5(3H)-diones that features a novel sequence of alkoxycarbonylation, acetone arylation, transamidation.
One-pot solvent-free synthesis of triaryl- and triheteroarylmethanes by Bi(OTf)3-catalyzed Friedel-Crafts reaction of arenes/heteroarenes with trialkyl orthoformates
Tuengpanya, Surisa,Chantana, Chayamon,Sirion, Uthaiwan,Siritanyong, Wipada,Srisook, Klaokwan,Jaratjaroonphong, Jaray
, p. 4373 - 4380 (2018/07/21)
A convenient, practical and highly efficient one-pot method has been developed for the synthesis of triaryl- and triheteroarylmethane derivatives by Bi(OTf)3-catalyzed Friedel-Crafts alkylation of trialkyl orthoformates in combination with a wide variety of arenes/heteroarenes at room temperature under solvent-free conditions and in an air atmosphere. The methodology offers an operational simplicity, high atom economy and environmentally benign procedure. Furthermore, selected compound 3k showed promising anti-inflammatory activity with inhibition nitric oxide and did not exhibit significant cytotoxic effects on macrophage cells.
Visible light mediated chemo-selective oxidation of benzylic alcohols
Devari, Shekaraiah,Rizvi, Masood Ahmad,Shah, Bhahwal Ali
supporting information, p. 3294 - 3297 (2016/07/11)
A highly chemoselective visible light mediated strategy has been developed for oxidation of benzylic alcohols. The method circumvents the use of toxic metal catalysts, high energy light source, and operates at room temperature. Furthermore reaction is easily scalable to gram levels.
Alkylbenzoquinone involved in development of cellular slime molds
Takaya, Yoshiaki,Hotta, Rie,Fujiwara, Kenshu,Otani, Risa,Uchiyama, Yurika,Sakakibara, Mizuki,Fukuda, Eri,Niwa, Masatake,Inouye, Kei,Oohata, Akiko A.
, p. 3660 - 3663 (2014/08/05)
The structure of the prespore-cell-promoting factor from Dictyostelium discoideum was determined to be 2-hydroxy-5-methyl-6-pentylbenzoquinone. The synthetic compound has prespore-cell-promoting activity similar to the natural one, with half-maximal induction at a concentration as low as 40 pM. It was also found that the factor induces aggregation in an aggregation-deficient mutant of a related species, Polysphodilium violaceum. Both these activities are sensitive to positional isomerism with the 6-methyl-5-pentyl isomer showing no detectable activity.
