cas 636-09-9, DIETHYL TEREPHTHALATE | Articles data

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Multi-colour electrochromic materials based on polyaromatic esters with low driving voltage
Low-cost single molecular electrochromic (EC) materials with low toxicity are desirable for EC displays and photonic devices. In this study, new EC materials based on phthalates, an inexpensive class of benzoate materials with relatively simple molecular structure, are designed and prepared. Despite being good candidates for EC devices due to clear colour changes when reduced, devices fabricated using phthalate derivatives (PDs) suffer from a high driving voltage. Herein, we propose a facile strategy of replacing the benzene core with polyaromatic esters to enlarge the conjugated area and to synthesise PDs to lower the driving voltage in EC devices. Additionally, devices show good memory effect (hundreds of seconds), the ability to undergo multiple colour changes and enhanced stability, dependent on the size of the conjugated bridge between the two sides of the molecule. The fabricated EC devices based on polyaromatic esters demonstrate a low driving voltage (-2.6 V). We have shown that the number of aromatic ester rings in the conjugated area is very critical to obtain different colours in this new class of EC materials. This series of EC materials has promising potential for future industry applications due to the vivid colour change upon electrochemical stimulation at a low driving voltage.
Zhang, Pengfei,Xing, Xing,Wang, Yueyi,Murtaza, Imran,He, Yaowu,Cameron, Joseph,Ahmed, Shuja,Skabara, Peter J.,Meng, Hong
p. 9467 - 9473
(2019)
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Synthesis and thermolysis of 3-substituted 3- trimethylsilylcyclopropenes
The synthesis of 3-substituted-3-(trimethylsilyl)cyclopropenes (X = CO2Et, CHO, CN) is described. Their acid sensitivity and thermal stability was probed and the reaction products were identified. In one case, a novel rearrangement to a Dewar furan maybe involved and this pathway was explored via kinetics and computations.
Arrowood, Tina L.,Kass, Steven R.
p. 6739 - 6748
(1999)
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Production of Copolyester Monomers from Plant-Based Acrylate and Acetaldehyde
PCTA is an important copolyester that has been widely used in our daily necessities. Currently, its monomers are industrially produced from petroleum-derived xylene. To reduce the reliance on fossil energy, we herein disclose an alternative route to acces
Yuan, Lin,Hu, Yancheng,Zhao, Zhitong,Li, Guangyi,Wang, Aiqin,Cong, Yu,Wang, Feng,Zhang, Tao,Li, Ning
supporting information

(2021/12/14)

Compound with AMPK agonistic activity and preparation and application of prodrug thereof
The invention relates to a compound with AMPK agonistic activity and a prodrug thereof, and as well as a preparation method and medical application of a prodrug thereof. The compound has the structure shown in the formula (I), and the prodrug of the compound has the structure shown in the formula (II), wherein each group and the substituent are as defined in the specification. The invention discloses a preparation method of the compound and application of the compound in prevention and treatment AMPK related diseases, and the AMPK related diseases include, but are not limited to, energy metabolism abnormality related diseases. Neurodegenerative diseases and inflammation-related diseases and the like.
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Paragraph 0145; 0151-0152; 0439-0442

(2021/10/27)

Nitrile Synthesis by Aerobic Oxidation of Primary Amines and in situ Generated Imines from Aldehydes and Ammonium Salt with Grubbs Catalyst
Herein, a Grubbs-catalyzed route for the synthesis of nitriles via the aerobic oxidation of primary amines is reported. This reaction accommodates a variety of substrates, including simple primary amines, sterically hindered β,β-disubstituted amines, allylamine, benzylamines, and α-amino esters. Reaction compatibility with various functionalities is also noted, particularly with alkenes, alkynes, halogens, esters, silyl ethers, and free hydroxyl groups. The nitriles were also synthesized via the oxidation of imines generated from aldehydes and NH4OAc in situ. (Figure presented.).
Utsumi, Tatsuki,Noda, Kenta,Kawauchi, Daichi,Ueda, Hirofumi,Tokuyama, Hidetoshi
supporting information
p. 3583 - 3588
(2020/08/05)

Photophysical, thermal properties, solvatochromism and DFT/TDDFT studies on novel conjugated D-A-π-A-D form of small molecules comprising thiophene substituted 1,3,4-oxadiazole
In this paper, we report the design and synthesis of a series of novel conjugated thiophene substituted 1,3,4-oxadiazole derivatives BSTO-4(a-f) of Donor-Acceptor-π-Acceptor-Donor form by utilizing palladium catalyzed Suzuki cross coupling reaction. Structures were characterized by using spectroscopic techniques namely FT-IR, 1H NMR, 13C NMR and Mass spectra. Their thermal, photophysical and solvatochromic properties were studied in detail. Also, the PL investigations in the solid state were carried out. Furthermore, theoretical calculations such as density functional theory (DFT) were performed to get a better understanding of the intramolecular charge transfer property and electronic structures of the compounds. Experimentally measured optical bandgap values are in the range 3.02 to 3.54 eV. All compounds exhibit Stokes shifts in the range of 2776–3964 cm?1 and fluorescence quantum yields (Φf) in the range of 0.06–0.70 in chloroform. These derivatives exhibit high thermal stability that is the 5% weight loss temperature of derivatives are in the range 178–356 °C and the compounds BSTO-4(b, e and f) had the glass transition temperatures (Tg) at 107 °C, 147 °C and 68 °C, respectively. These results demonstrate that the novel thiophene substituted 1,3,4-oxadiazole compounds are promising candidates for potential applications in development of OLEDs, organic electronic devices/optoelectronic devices.
Najare, Mahesh S.,Patil, Mallikarjun K.,Nadaf, AfraQuasar A.,Mantur, Shivaraj,Garbhagudi, Manjunatha,Gaonkar, Supreet,Inamdar, Sanjeev R.,Khazi, Imtiyaz Ahmed M.
(2019/09/18)

The sustainable room temperature conversion of: P -xylene to terephthalic acid using ozone and UV irradiation
Current industrial processes utilize Co/Mn bromides as catalysts to catalyze the oxidative conversion of para-xylene to terephthalic acid (TA) in acetic acid at high temperatures (>200 °C, air, 15-30 atm.). The decomposition of metallo-catalysts and solvents at high temperatures as well as a subsequent hydropurification process releases thousands of millions of tons of wastewater, global warming gas (CO2) and ozone depleting gas (CH3Br) into the global environment per year, causing global warming, ozone depletion, dramatic climate change, huge economic losses, and many other environmental problems. Herein, we report an alternative sustainable process with low energy demand for the room temperature oxidative conversion of p-xylene to terephthalic acid, with 96% TA yield and 98% selectivity, via ozone treatment and concurrent UV irradiation and without the generation and release of greenhouse gas (CO2), ozone depleting gas (CH3Br), and wastewater, or the need for a high energy-demand hydropurification process. The reaction mechanism involves the singlet O(1D)- and hydroxyl radical-mediated selective C-H functionalization of p-xylene.
Hwang, Kuo Chu,Sagadevan, Arunachalam,Kundu, Pradip
supporting information
p. 6082 - 6088
(2019/11/20)

Electrocarboxylation of halobenzonitriles: An environmentally friendly synthesis of phthalate derivatives
This manuscript presents an efficient approach for producing high valuable compounds using CO2 as building block. The methodology employed is based on electrochemical techniques, which allow performing eco-friendly chemistry solutions and maintaining the aim of offering a potential long-term strategy for reducing the CO2 emissions in the atmosphere, while obtaining useful compounds, such as aromatic acids and phthalate derivatives. This work describes the electrochemical reduction behavior of 4-halobenzonitrile compounds using Glassy Carbon and Silver as cathodes under inert and carbon dioxide atmosphere. Controlled potential electrolysis of 4-halobenzonitriles under CO2 allows obtaining, in very good yields, the corresponding mono- and di-carboxylated organic compounds in CO2-saturated solutions of dimethylformamide containing 0.1 M of tetrabutylammonium tetrafluoroborate. Electro-catalytic effects are seen when Ag is used a cathode, which give very high yields, especially as regards di-carboxylated products. The methodology offers a new “green” route for the synthesis of different phthalate derivatives, which can be potentially used for making plastic polymers in a more environmentally friendly way.
Reche, Irene,Mena, Silvia,Gallardo, Iluminada,Guirado, Gonzalo
(2019/08/02)

Methods for preparing esters from crotonaldehyde and formaldehyde
The invention relates to methods for preparing esters from crotonaldehyde and formaldehyde. The preparation method for benzoate or phthalate comprises the following steps: step 1, subjecting crotonaldehyde, formaldehyde and acrylate (or maleate and fumarate) to a D-A cycloaddition reaction under base catalysis so as to produce ester group-substituted cyclohexene formaldehyde; and step 2, subjecting a resulting product to decarbonylation/aromatization under the action of a transition metal catalyst to produce benzoate or phthalate. The preparation method for terephthalate or trimellitate comprises the following steps: step 1, subjecting crotonaldehyde, formaldehyde and acrylate (or maleate and fumarate) to a D-A cycloaddition reaction under base catalysis so as to produce ester group-substituted cyclohexene formaldehyde; step 2, subjecting aldehyde groups on the resulting product to selective oxidation so as to produce carboxylic acid; step 3, carrying out esterification under acid catalysis so as to obtain ester group-substituted cyclohexene; and step 4, carrying out aromatization under the action of a transition-metal catalyst so as to produce terephthalate or trimellitate.
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(2018/06/26)

Activating cobalt nanoparticles via the Mott-Schottky effect in nitrogen-rich carbon shells for base-free aerobic oxidation of alcohols to esters
Heterogeneous catalysts of inexpensive and reusable transition-metal are attractive alternatives to homogeneous catalysts; the relatively low activity of transition-metal nanoparticles has become the main hurdle for their practical applications. Here, the de novo design of a Mott-Schotfky-type heterogeneous catalyst is reported to boost the activity of a transition-metal nanocatalyst through electron transfer at the metal/nitrogen-doped carbon interface. The Mott-Schottky catalyst of nitrogen-rich carbon-coated cobalt nanoparticles (Co@NC) was prepared through direct polycondensation of simple organic molecules and inorganic metal salts in the presence of g-C3N4 powder. The Co@NC with controllable nitrogen content and thus tunable Fermi energy and catalytic activity exhibited a high turnover frequency (TOF)value (8.12 mol methyl benzoate mol-1 Co h-1) for the direct, base-free, aerobic oxidation of benzyl alcohols to methyl benzoate; this TOF is 30-fold higher than those of the state-of-the-art transitionmetal-based nanocatalysts reported in the literature. The presented efficient Mott-Schottky catalyst can trigger the synthesis of a series of alkyl esters and even diesters in high yields.
Su, Hui,Zhang, Ke-Xin,Zhang, Bing,Wang, Hong-Hui,Yu, Qiu-Ying,Li, Xin-Hao,Antonietti, Markus,Chen, Jie-Sheng
p. 811 - 818
(2017/05/17)

Graphene Oxide: An Efficient Acid Catalyst for the Construction of Esters from Acids and Alcohols
Graphene oxide was found to be an efficient and reusable acid catalyst for the esterification reaction. A wide range of aliphatic and aromatic acids and alcohols were compatible with the standard conditions and afforded the corresponding products in good yields. The heterogeneous catalyst can be easily recovered and recycled in dichloro-ethane solvent with good catalytic activity.
Chen, Zhengwang,Wen, Yuelu,Fu, Yejuan,Chen, Hai,Ye, Min,Luo, Guotian
supporting information
p. 981 - 985
(2017/05/05)

DBU-Based Dicationic Ionic Liquids Promoted Esterification Reaction of Carboxylic Acid with Primary Chloroalkane Under Mild Conditions
Abstract: A series of DBU-based (DBU = 1, 8-diazabicyclo [5.4.0] undec-7-ene) dicationic ionic liquids with different anions were successfully synthesized by the reaction of DBU and 1, 6-dichlorohexane. Therein, the dicationic ionic liquid 1, 1′-(hexane-1, 6-diyl)bis(1, 8-diazabicyclo [5.4.0]undec-7-enium) dichlorine (IL-1) was successfully employed as an efficient catalyst in esterification reaction of carboxylic acids with primary chloroalkanes under mild conditions without any additional basic reagents. Moreover, the optimum catalyst could be efficiently reused for five times without any significant change on the catalytic effect. The improved protocol is not only efficient, but also green and pollution-free.
Liu, Yang,Mao, Guijie,Zhao, Hongyan,Song, Jinyi,Han, Huatao,Li, Zhuofei,Chu, Wenyi,Sun, Zhizhong
p. 2764 - 2771
(2017/09/14)

Diethyloxalate as “CO” Source for Palladium-Catalyzed Ethoxycarbonylation of Bromo- and Chloroarene Derivatives
Palladium(II)-catalyzed ethoxycarbonylation of aryl bromides with diethyloxalate oxalate is described. Functionalized aromatic esters can be efficiently synthesized with only 0.65 mol % PdCl2(PPh3)2 catalyst under microwav
Monrose, Amandine,Salembier, Helori,Bousquet, Till,Pellegrini, Sylvain,Pélinski, Lydie
supporting information
p. 2699 - 2704
(2017/08/16)

Cobalt-Catalyzed Esterification of Amides
The first cobalt-catalyzed amide activation of N-Boc-amides, and their conversion into esters, is reported here. This new methodology presents a very practical process that does not require an inert atmosphere, uses an inexpensive cobalt catalyst, and proceeds under mild reaction conditions. This catalytic system has a broad substrate scope and has been shown to be highly efficient, with catalyst loadings as low as 1 mol %.
Bourne-Branchu, Yann,Gosmini, Corinne,Danoun, Grégory
supporting information
p. 10043 - 10047
(2017/08/01)

Preparation method of terephthalic acid and diester thereof
The invention discloses a preparation method of terephthalic acid and diester thereof. Specifically, under the action of a supported metal catalyst, 2-cyclohexene-1,4-dicarboxylic acid undergoes catalytic dehydro-aromatization in a polar solvent or a nonpolar solvent so as to prepare terephthalic acid and diester. The polar solvent is water, methanol, ethanol, n-propanol, isopropanol, n-butanol, glycol dimethyl ether and diglyme. The nonpolar solvent is one or more than two components selected from a group consisting of n-hexane, n-heptane, normal octane, cyclohexane, benzene and toluene. A metal active component of the supported metal catalyst is non-noble metal and/or noble metal. A carrier for the supported metal catalyst is one or more than two components selected from a group consisting of a carbon carrier, nanoscale metal oxide, nanometer nonmetal oxide and a molecular sieve. When conversion rate of 2-cyclohexene-1,4-dicarboxylic acid is 95% and above, selectivity of terephthalic acid or diester of terephthalic acid can reach 90%.
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Paragraph 0025-0026

(2017/06/23)

Production of Diethyl Terephthalate from Biomass-Derived Muconic Acid
We report a cascade synthetic route to directly obtain diethyl terephthalate, a replacement for terephthalic acid, from biomass-derived muconic acid, ethanol, and ethylene. The process involves two steps: First, a substituted cyclohexene system is built through esterification and Diels-Alder reaction; then, a dehydrogenation reaction provides diethyl terephthalate. The key esterification reaction leads to improved solubility and modulates the electronic properties of muconic acid, thus promoting the Diels-Alder reaction with ethylene. With silicotungstic acid as the catalyst, nearly 100 % conversion of muconic acid was achieved, and the cycloadducts were formed with more than 99.0 % selectivity. The palladium-catalyzed dehydrogenation reaction preferentially occurs under neutral or mildly basic conditions. The total yield of diethyl terephthalate reached 80.6 % based on the amount of muconic acid used in the two-step synthetic process.
Lu, Rui,Lu, Fang,Chen, Jiazhi,Yu, Weiqiang,Huang, Qianqian,Zhang, Junjie,Xu, Jie
supporting information
p. 249 - 253
(2016/01/25)

Processes and catalysts for conversion of 2,5-dimethylfuran derivatives to terephthalate
A process of making terephthalic acid or a derivative of terephthalic acid is described. The process includes reacting a derivative of 2,5-dimethylfuran, with a dienophile containing an unsaturated 2-carbon unit, in the presence of a catalyst having Br?nsted acidity to form a para-xylene derivative; and optionally reacting the para-xylene derivative to terephthalic acid.
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Page/Page column 10-12; 14

(2016/05/19)

Conversion of a metal-organic framework to N-doped porous carbon incorporating Co and CoO nanoparticles: Direct oxidation of alcohols to esters
A Co-based metal-organic framework, ZIF-67, has been exploited as a selflate to afford N-doped porous carbon incorporating Co NPs with surface-oxidized CoO species, which exhibit excellent catalytic activity, selectivity and magnetic recyclability toward the direct oxidation of alcohols to esters with O2 as a benign oxidant under mild conditions.
Zhou, Yu-Xiao,Chen, Yu-Zhen,Cao, Lina,Lu, Junling,Jiang, Hai-Long
supporting information
p. 8292 - 8295
(2015/05/13)

Highly selective trifluoroacetic ester/ketone metathesis: An efficient approach to trifluoromethyl ketones and esters
A highly selective and atom efficient 'trifluoroacetic ester/ketone metathesis' has been sincerely witnessed. Enolizable alkyl (at least two non-hydrogen atoms) aryl ketones were found to react readily with ethyl trifluoroacetate under the promotion of NaH to afford trifluoroacetic ester/ketone exchange products, trifluoromethyl ketones (TFMKs), and aromatic acid esters, which were quite different from the general Claisen condensation products, 1,3-diketones. The outcome of the reaction between ketone and ethyl trifluoroacetate is strongly related to the structures of substrates, the steric congestion caused by alkyl group is in favor of the C-C bond cleavage. DFT investigation further disclosed that the metathesis reaction was a kinetically favored pathway. Using only a slight excess of cheap trifluoromethylation reagent, simple operation and mild conditions make it a practical method for preparation of TFMKs on large scale, as well as a new choice of converting aryl alkyl ketones to aromatic acid esters.
Zhou, Yuhan,Yang, Dongmei,Luo, Gen,Zhao, Yilong,Luo, Yi,Xue, Na,Qu, Jingping
p. 4668 - 4674
(2014/06/23)

Polymer supported Pd catalyzed carbonylation of aryl bromides for the synthesis of aryl esters and amides
A polymer-anchored palladium(ii) catalyst was synthesized and characterized using various spectroscopic techniques. Its catalytic activity was evaluated for the alkoxycarbonylation and aminocarbonylation reactions. These carbonylation reactions were carried out for various substituted aryl bromides using alcohols and amines. Both the reactions were optimized by varying the bases, temperature and solvents. These experiments were carried out under high CO pressure. The catalyst was very stable and can be facilely recovered and reused six times without a significant decrease in its activity and selectivity. the Partner Organisations 2014.
Islam, Sk Manirul,Ghosh, Kajari,Roy, Anupam Singha,Molla, Rostam Ali
p. 38986 - 38999
(2014/11/07)

Dinuclear vanadium, copper, manganese and titanium complexes containing O,O,N-dichelating ligands: Synthesis, crystal structure and catalytic activity
O,O,N-or O,N-dichelating ligands, H4L1, H 4L2, derived from new bis(hydroxybenzylidene)-substituted terephthalo and oxalo hydrazides were prepared and characterized by FT-IR and NMR spectroscopy (H4-L1 = dicondensation of salicylaldehyde and terephthalic acid dihydrazide, H4L2 = dicondensation of sali-cylaldehyde and oxalic acid dihydrazide). [{VO 2}2(H2L1)] (1), [{Cu(CH 3OH)}2(L1)] (2), [{Mn(CH3OH)} 2(L1)] (3) and [TiO(H3L1) 2] (4) complexes of the potentially hexadentate 2[ONO] donor hydrazone ligand [L1]4 were synthesized by reaction of the appropriate metal salts with H4L1. The complexes [{VO(CH3O)(CH3OH)}2(L2)] (5), [{Cu(CH3OH)}2(L2)] (6), [{Mn(H 2O)2(CH3OH)}2(L2)] (7) and [{TiO(CH3OH)}2(L2)]·2H2O (8) were synthesized by the reaction of corresponding metal salts with H 4L2. All complexes were characterized by microanalyses, FT-IR, UV-Vis and NMR spectroscopic methods. The crystal structures of 1 and 5 were established by X-ray analyses. Compound 1 is a one-dimensional coordination polymer. The catalytic potential of the complexes was evaluated for oxidation of hydrocarbons including cycloalkenes, cyclic alkanes and benzylalcohol using H2O2 as terminal oxidant. Of the studied aroylhydrazone complexes, 4 showed the best selectivity and activity as catalyst.
Hosseini-Monfared, Hassan,Asghari-Lalami, Nasim,Pazio, Aleksandra,Wozniak, Krzysztof,Janiak, Christoph
p. 241 - 250
(2013/10/22)

Cobalt carbonyl as an effective CO source in one-pot synthesis of esters from aryl halides
For the first time, we have successfully applied Co2(CO) 8 as an effective carbonyl source for the Pd catalysed alkoxycarbonylation of aryl halides affording the corresponding aryl esters under mild microwave conditions. A wide variety of esters and carbonyl derivatives were prepared using this protocol.
Baburajan,Senthilkumaran,Elango, Kuppanagounder P.
p. 3050 - 3056
(2013/10/01)

Synthesis and characterization of schiff base metal complexes and reactivity studies with malemide epoxy resin
A novel malemide epoxy containing Co(II), Ni(II) and Cu(II) ions have been synthesized by curing malemide epoxy resin (MIEB-13) and Co(II), Ni(II) and Cu(II) complexes of macrocyclic bis-hydrazone Schiff base. The Schiff base was synthesized by reacting 1,4-dicarbnyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol. The Schiff base and its Co(II), Ni(II) and Cu(II) complexes have been characterized by elemental analyses, spectral (IR, 1H NMR, UV-vis., FAB mass, ESR), thermal and magnetic data. The curing reaction of maleimide epoxy compound with metal complexes was studied as curing agents. The stability of cured samples was studied by thermo-gravimetric analyses and which have excellent chemical (acid/alkali/solvent) and water absorption resistance. Further, the scanning electron microscopy (SEM) and definitional scanning colorimetric (DSC) techniques were confirmed the phase homogeneity of the cured systems.
Lakshmi,Shivananda,Prakash, Gouda Avaji,Isloor, Arun M,Mahendra
experimental part
p. 473 - 482
(2012/05/04)

A clean, palladium-catalyzed oxidative esterification of aldehydes using benzyl chloride
A highly efficient, mild, simple and clean procedure is presented for the one-pot oxidation of aromatic and aliphatic aldehydes to their corresponding ethyl esters using benzyl chloride as the oxidant under palladium-catalyzed conditions. The reaction is complete in just 30 min under microwave irradiation and inert conditions are not required to obtain good to excellent yields (65-93%) of isolated products.
Heropoulos, Georgios A.,Villalonga-Barber, Carolina
experimental part
p. 5319 - 5322
(2011/10/31)

Base-induced mechanistic variation in palladium-catalyzed carbonylation of aryl iodides
A mechanism, which is distinct from the traditional one when sodium alkoxide was used instead of tertiary amines, was proposed for the alkoxycarbonylation of aryl iodides. The catalytic cycle was composed of oxidative addition, subsequent ArPdOR formation, CO insertion to Pd-OR, and final reductive elimination of ArPdCOOR. The kinetic simultaneity of the formation of deiodinated side product from the aryl iodide and aldehyde from corresponding alcohol provided strong evidence for the existence of ArPdOR species. The observation of thioether, as the other competitive product in palladium catalyzed thiocarbonylation of aryl iodides and sodium alkylthiolate, also indicate the possibility of metathesis between ArPdl and sodium alkylthiolate. Preliminary kinetic studies revealed that neither oxidative addition nor reductive elimination was rate limiting. DFT calculation displayed preference for CO insertion into Pd-OR bond. The advantage of this novel mechanism had been demonstrated in the facile alkoxycarbonylation and thiocarbonylation. The ethoxycarbonylation of aryl iodides under room temperature and balloon pressure of CO in the presence of EtONa were examined, and good to high yields were obtained; the t-butoxycarbonylation reactions in the presence of t-BuONa were achieved, and the alkylthiocarbonylation (including the t-butylthiocarbonylation) of aryl iodides in the presence of sodium alkylthiolate were also investigated.
Hu, Yanhe,Liu, Jing,Lu, Zhixin,Luo, Xiancai,Zhang, Heng,Lan, Yu,Lei, Aiwen
supporting information; experimental part
p. 3153 - 3158
(2010/05/15)

Microwave-assisted carbonylation and cyclocarbonylation of aryl iodides under ligand free heterogeneous catalysis
"Chemical Equation Presented" Carbonylation reaction is a very effective transformation for the synthesis of esters, amides, and heterocyclic compounds. Heterogeneous catalyzed carbonylation reactions can be carried out using the association of Pd/C and microwave dielectric heating. Alkoxy carbonylation can be performed, with stoichiometric amounts of different primary and secondary alcohols in DMF in the presence of DBU as the base. Analogously, iodobenzene, CO, and amines can be transformed into the corresponding amides in good yields after a simple filtration to remove the catalyst. Pd/C was also successfully employed in microwave-assisted cyclocarbonylation of o-iodoaniline with acyl chlorides to give benzoxazinones. Pd/ C can be recycled two times without, a considerable difference in the reaction yields.
Salvadori, Jessica,Balducci, Evita,Zaza, Silvia,Petricci, Elena,Taddei, Maurizio
experimental part
p. 1841 - 1847
(2010/06/11)

Synthesis, spectral characterization, in-vitro microbiological evaluation and cytotoxic activities of novel macrocyclic bis hydrazone
A macrocyclic hydrazone Schiff base was synthesized by reacting 1,4-dicarbonyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol and a series of metal complexes with this new Schiff base were synthesized by reaction with Co(II), Ni(II) and Cu(II) metal salts. The Schiff base and its complexes have been characterized by elemental analyses, IR, 1H NMR, UV-vis, FAB mass, ESR spectra, fluorescence, thermal, magnetic and molar conductance data. The analytical data reveal that the Co(II), Ni(II) and Cu(II) complexes possess 2:1 metal-ligand ratios. All the complexes are non-electrolytes in DMF and DMSO due to their low molar conductance values. Infrared spectral data suggest that the hydrazone Schiff base behaves as a hexadentate ligand with NON NON donor sequence towards the metal ions. The ESR spectral data shows that the metal-ligand bond has considerable covalent character. The electrochemical behavior of the copper(II) complex was investigated by cyclic voltammetry. The Schiff base and its complexes have also been screened for their antibacterial (Escherichia coli, Staphylococcus aureus, Shigella dysentery, Micrococcus, Bacillus subtilis, Bacillus cereus and Pseudomonas aeruginosa) and antifungal activities (Aspergillus niger, Penicillium and Candida albicans) by MIC method. The brine shrimp bioassay was also carried out to study their in-vitro cytotoxic properties.
Avaji, Prakash Gouda,Vinod Kumar,Patil, Sangamesh A.,Shivananda,Nagaraju
experimental part
p. 3552 - 3559
(2009/12/04)

Synthesis of aromatic esters via Pd-catalyzed decarboxylative coupling of potassium oxalate monoesters with aryl bromides and chlorides
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Shang, Rui,Fu, Yao,Li, Jia-Bin,Zhang, Song-Lin,Guo, Qing-Xiang,Liu, Lei
supporting information; experimental part
p. 5738 - 5739
(2009/09/25)

Synthesis of a novel β-diketone containing carbazole and 2,5-diphenyl-1,3,4-oxadiazole fragments
A novel β-diketone containing carbazole and 2,5-diphenyl-1,3,4- oxadiazole fragments as hole- and electron-transporting functional groups, respectively, was synthesized via efficient and convenient procedure. The product attracts interest from the viewpoint of its potential applications as optoelectronic material.
Tang, Huaijun,Zhang, Zhiguo,Cong, Changjie,Zhang, Keli
body text
p. 559 - 563
(2009/09/06)

Palladium-catalyzed oxidative carbonylation of alkyl and aryl indium reagents with CO under mild conditions
CO now can react with organoindium reagents. A novel palladium-catalyzed oxidative carbonylation reaction of organoindium reagents by CO gas with desyl chloride as oxidant was developed in supplementation with the classical methods for preparation of carboxylic acid derivatives. Primary, secondary alkyl indium reagents with β-hydrogens and aryl indium reagents were suitable substrates, and the reaction could be carried out at 60°C under 50 psi CO. Carbonylation of alkyl indium reagents can occur smoothly without additional base. Although the indium reagents were prepared from corresponding Grignard reagents (at low temperature), they displayed full compatibility with various functional groups under the protic reaction conditions. Preliminary mechanistic studies including stoichiometric and catalytic reaction examination provided evidence to support the operation of the mechanism consisted of oxidative addition of deslyl chloride to Pd(0) and quick tautomerization to give a palladium enolate species II (ROPdCl), displacement of the enolate group in II by R2OH, followed by CO insertion to give alkoxycarbonyl palladium complex V, which undergoes transmetalation with R13ln and reductive elimination to afford the product and a Pd(0) species. In this mechanism, the alkoxycarbonyl group was transferred to the palladium center prior to the alkyl group, different from traditional ways initiated from oxidative addition of alkyl halides to a Pd(0) species.
Zhao, Yingsheng,Jin, Liqun,Li, Peng,Lei, Aiwen
supporting information; body text
p. 9429 - 9433
(2009/02/03)

Alkoxycarbonylation of aryl iodides catalyzed by Pd with a thiourea type ligand under balloon pressure of CO
Palladium-catalyzed alkoxycarbonylation of aryl iodides with a thiourea-oxazoline type ligand has been achieved under mild conditions. Various functional groups were tolerated and the yields were from moderate to excellent.
Liu, Jing,Liang, Bo,Shu, Dongxu,Hu, Yanhe,Yang, Zhen,Lei, Aiwen
p. 9581 - 9584
(2008/12/22)

Preparation of monoalkyl terephthalates: An overview
Terephthalic acid can be readily converted to the corresponding monoalkyl terephthalate in high yield, via a two-step procedure. This method is advantageously compared to the more representative methods described in the literature. The purification of the expected monoester, a crucial problem for this synthetic pathway, is discussed, and an original procedure has been developed. Copyright Taylor & Francis Group, LLC.
Chenot, Elodie-Denise,Bernardi, Dan,Comel, Alain,Kirsch, Gilbert
p. 483 - 490
(2007/10/03)

A chemical procedure for reprocessing of poly(ethylene terephthalate) waste
A procedure was developed for degradation of poly(ethylene terephthalate) waste with water to the starting monomers. The possibility of preparing diethyl terephthalate without a catalyst in a rocking cylindrical pressure vessel with the rocking axis passing through the geometric center was examined.
Mitrofanov,Bochkarev,Sevodin
p. 992 - 994
(2008/09/19)

An efficient catalyst for PD-catalyzed carbonylation of aryl arenesulfonates
(Chemical Equation Presented) Aryl carboxylic esters were synthesized by Pd-catalyzed carbonylation of aryl p-fluorobenzenesulfonates or -tosylates. A unique Josiphos ligand was discovered through high-throughput catalyst screening, which was the key for the successful carbonylation of various substrates. This catalyst is effective and works well for both electron-rich and electron-poor aryl arenesulfonates. Isolated yields of up to 90% were obtained for aryl p-fluorobenzenesulfonates and -tosylates.
Cai, Chaoxian,Rivera, Nelo R.,Balsells, Jaume,Sidler, Rick R.,McWilliams, J. Christopher,Shultz, C. Scott,Sun, Yongkui
p. 5161 - 5164
(2007/10/03)

A simple and facile carboxylation method and its application for synthesis of liquid crystals
Sonication of a mixture of magnesium powder, 1,2-dibromoethane, aryl bromide and diethyl dicarbonate in THF followed by treatment with BF 3·OEt2 at room temperature afforded aryl ester with reasonable yield. A series of aryl bromides were investigated and transformed to their corresponding aryl esters under the reaction conditions.
Lee, Adam Shih-Yuan,Wu, Chih-Chiang,Lin, Li-Shin,Hsu, Hsiu-Fu
p. 568 - 572
(2007/10/03)

Process for producing cyanobenzoic acid derivatives
A process for producing a cyanobenzoic acid compound, a cyanobenzamide compound, an alkyl cyanobenzoate compound, and a cyanobenzoyl chloride compound, which are useful intermediates for a variety of chemicals such as pharmaceuticals, agrochemicals, liquid crystals, and monomers for functional polymers. One nitrile group of an easily available phthalonitrile compound is selectively hydrolyzed to thereby produce a cyanobenzamide compound with high selectivity and yield. The cyanobenzamide compound thus-produced is transformed under acidic conditions into a cyanobenzoic acid compound and a cyanobenzoate ester compound without the cyano group of the benzene ring being damaged.
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(2008/06/13)

Palladium-catalyzed alkoxycarbonylation of aryl p-toluenesulfonate
Methyl- and ethyl arylcarboxylates were synthesized by palladium-catalyzed alkoxycarbonylation of various aryl p-toluenesulfonates (tosylates). Yields were highly dependent on the substituent of aryl tosylates and phosphine ligands used. Ethoxycarbonylation of 4-acetylphenyl tosylate by the use of a bisphosphine ligand gave ethyl 4-acetylbenzoate in quite satisfactory yields.
Kubota, Yoshihiro,Nakada, Shigekuni,Sugi, Yoshihiro
p. 183 - 185
(2007/10/03)

Process for the preparation of bis(amidocarboxylic acids)
A process is reported for the preparation of bis(amidocarboxylic acid) involving reacting an ester with an aminocarboxylate compound, the latter being formed from lactams or aminocarboxylic acids and salts thereof. The ester and aminocarboxylate compound are present in a weight ratio of about 1:1 to about 1:4, and reaction is conducted in a mono- or polyhydric alcohol solvent.
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(2008/06/13)

1,4-Dicarbonyl-2,5-cyclohexadiene
The mechanism of the photolysis of paracyclophane-1,10-dione (9) was investigated in solution and in argon matrices.The first step of the photolysis involves α-cleavage of the cyclophane yielding a diradical 11 which could be trapped by ethanol.In argon at 10 K the diradical rapidly splits into p-xylylene (10) and 1,4-dicarbonyl-2,5-cyclohexadiene (7) and therefore was not directly observed by spectroscopic methods.The bisketene 7 was characterized by comparison of the experimantal and calculated IR spectrum. - Keywords: Ketenes / Matrix isolation / Calculations, ab initio
Marquardt, Ralph,Sander, Wolfram,Laue, Thomas,Hopf, Henning
p. 1643 - 1648
(2007/10/02)

Unsymmetrical dicarboxylic esters as bleach precursors
A bleach precursor compound, its peroxygen derivative, and detergent compositions containing these materials are disclosed herein. The bleach precursors structurally comprise a pair of different diesters, one ester containing an electrically-charged functional group. Perhydrolysis of the precursor in the presence of hydrogen peroxide and a basic aqueous media generates a peroxycarboxylic acid.
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(2008/06/13)

Tetralin esters of phenols or benzoic acids having retinoid like activity
Retinoid-like activity is exhibited by compounds of the formula STR1 where the R groups are independently hydrogen, or lower alkyl; A is --C(O)O--, --OC(O)--, --C(O)S--, or --SC(O)--; n is 0-5; and Z is H, --COB where B is --OH or a pharmaceutically acceptable salt, or B is --OR 1 where R 1 is an ester-forming group, or B is --N(R) 2 where R is hydrogen or lower alkyl, or Z is --OE where E is hydrogen or an ether-forming group or --COR 2 where R 2 is hydrogen, lower alkyl, phenyl or lower alkyl phenyl, or Z is --CHO or an acetal derivative thereof, or Z is --COR 3 where R 3 is --(CH 2) m CH 3 where m is 0-4 and the sum of n and m does not exceed 4.
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(2008/06/13)

TRANSITION METAL COMPLEX CATALYZED CARBONYLATION OF ORGANIC HALIDES IN THE PRESENCE OF MOLECULAR SIEVES INSTEAD OF BASE
In the presence of molecular sieves under base free conditions organic halides are successfully carbonylated under carbon monoxide pressure with water or alcohols catalyzed by Co or Pd complex to generate the corresponding carboxylic acids or esters, respectively, in good yields.
Urata, Hisao,Hu, Nan-Xing,Maekawa, Hisayuki,Fuchikami, Takamasa
p. 4733 - 4736
(2007/10/02)

Thiochroman esters of phenols and terephthallates having retinoid-like activity
Compounds of formula I STR1 in which: the R groups are independently hydrogen or lower alkyl; one of A and B is O or S and the other is --C(O)--, A being attached to the thiochroman ring at the 6 or 7-position;n is 0-5; andZ is H, an acid or acid derivative, an alcohol or alcohol derivative, acetal or acetal derivative or ketone or ketone derivative, or a pharmaceutically acceptable salt, have retinoid-like activity.
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(2008/06/13)

HYDROLYSIS IN THE ABSENCE OF BULK WATER 1. CHEMOSELECTIVE HYDROLYSIS OF AMIDES USING TETRAHALOPHTALIC ANHYDRIDES
The reaction of primary and secondary amides with tetrafluorophthalic or tetrachlorophtalic anhydride gives carboxylic acids in good yield.The reaction is chemoselective in that the amide functionality can be hydrolyzed in the presence of ester groups.
Eaton, Jefferson T.,Rounds, William D.,Urbanowicz, John H.,Gribble, Gordon W.
p. 6553 - 6556
(2007/10/02)