27982-06-5Relevant articles and documents
Mustard Carbonate Analogues as Sustainable Reagents for the Aminoalkylation of Phenols
Annatelli, Mattia,Trapasso, Giacomo,Salaris, Claudio,Salata, Cristiano,Castellano, Sabrina,Aricò, Fabio
supporting information, p. 3459 - 3464 (2021/05/24)
N,N-dialkyl ethylamine moiety can be found in numerous scaffolds of macromolecules, catalysts, and especially pharmaceuticals. Common synthetic procedures for its incorporation in a substrate relies on the use of a nitrogen mustard gas or on multistep syntheses featuring chlorine hazardous/toxic chemistry. Reported herein is a one-pot synthetic approach for the easy introduction of aminoalkyl chain into different phenolic substrates through dialkyl carbonate (β-aminocarbonate) chemistry. This new direct alcohol substitution avoids the use of chlorine chemistry, and it is efficient on numerous pharmacophore scaffolds with good to quantitative yield. The cytotoxicity via MTT of the β-aminocarbonate, key intermediate of this synthetic approach, was also evaluated and compared with its alcohol precursor.
Aryl Ether Syntheses via Aromatic Substitution Proceeding under Mild Conditions
Ando, Shin,Tsuzaki, Marina,Ishizuka, Tadao
, p. 11181 - 11189 (2020/10/12)
In this study, mild conditions for aromatic substitutions during the syntheses of aryl ethers were developed. In the reaction conditions, the choices of solvent, base, and the sequence for the addition of the reagents proved important. A wide variety of alcohols were used directly as nucleophiles and smoothly reacted with aryl chlorides that possessed either a nitro or a cyano group at either the ortho- or para-position. Controlled experiments we performed suggested that the reaction underwent a charge-transfer process mediated by a combination of DMF and tert-BuOK.
Chemoselective Synthesis of Aryl Ketones from Amides and Grignard Reagents via C(O)-N Bond Cleavage under Catalyst-Free Conditions
Sureshbabu, Popuri,Azeez, Sadaf,Muniyappan, Nalluchamy,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
, p. 11823 - 11838 (2019/10/02)
Conversion of a wide range of N-Boc amides to aryl ketones was achieved with Grignard reagents via chemoselective C(O)-N bond cleavage. The reactions proceeded under catalyst-free conditions with different aryl, alkyl, and alkynyl Grignard reagents. α-Ketoamide was successfully converted to aryl diketones, while α,β-unsaturated amide underwent 1,4-addition followed by C(O)-N bond cleavage to provide diaryl propiophenones. N-Boc amides displayed higher reactivity than Weinreb amides with Grignard reagents. A broad substrate scope, excellent yields, and quick conversion are important features of this methodology.
Novel palladium nanoparticles supported on β-cyclodextrin@graphene oxide as magnetically recyclable catalyst for Suzuki–Miyaura cross-coupling reaction with two different approaches in bio-based solvents
Heidari, Bahareh,Heravi, Majid M.,Nabid, Mohammad Reza,Sedghi, Roya,Hooshmand, Seyyed Emad
, (2018/11/23)
A novel nanocatalyst was designed and prepared. Initially, the surface of magnetic graphene oxide (M-GO) was modified using thionyl chloride, tris(hydroxymethyl)aminomethane and acryloyl chloride as linkers which provide reactive C═C bonds for the polymerization of vinylic monomers. Separately, β-cyclodextrin (β-CD) was treated with acryloyl chloride to provide a modified β-CD. Then, in the presence methylenebisacrylamide as a cross-linker, monomers of modified β-CD and acrylamide were polymerized on the surface of the pre-prepared M-GO. Finally, palladium acetate and sodium borohydride were added to this composite to afford supported palladium nanoparticles. This fabricated nanocomposite was fully characterized using various techniques. The efficiency of this easily separable and reusable heterogeneous catalyst was successfully examined in Suzuki–Miyaura cross-coupling reactions of aryl halides and boronic acid as well as in modified Suzuki–Miyaura cross-coupling reactions of N-acylsuccinimides and boronic acid in green media. The results showed that the nanocatalyst was efficient in coupling reactions for direct formation of the corresponding biphenyl as well as benzophenone derivatives in green media based on bio-based solvents. In addition, the nanocatalyst was easily separable, using an external magnet, and could be reused several times without significant loss of activity under the optimum reaction conditions.
Kinetic studies on tetrabutylammonium bromochromate oxidation of some mono-and di-substituted benzhydrols
Hemalatha,Asghar, Basim H.,Mansoor, S Sheik
, p. 821 - 826 (2018/03/13)
The oxidation of 12 mono- and di-substituted benzhydrols (BH) by tetrabutylammonium bromochromate (TBABC) have been studied in aqueous acetic acid medium. Absence of any effect of added acrylonitrile on the reaction discounts the possibility of a one-electron oxidation, leading to the formation of free radicals. The tetrabutylammonium bromochromate oxidation of 12 mono- and di-substituted benzhydrols complies with the isokinetic relationship and Hammett relationship. The overall mechanism is proposed to involve a cyclic concerted symmetrical transition state leading to the product.
Synthesis of diaryl ketones through oxidative cleavage of the C-C double bonds in N -Sulfonyl enamides
Kim, Hyunseok,Park, Sangjune,Baek, Yonghyeon,Um, Kyusik,Han, Gi Uk,Jeon, Da-Hye,Han, Sang Hoon,Lee, Phil Ho
, p. 3486 - 3496 (2018/04/14)
An oxidative cleavage of a C-C double bond is developed from the photochemical [2+2]-cycloaddition of diaryl N-tosyl enamides, aryl heteroaryl N-tosyl enamides, and N-tosyl cyclic enamides with singlet molecular oxygen, followed by a ring-opening reaction mediated by Cs2CO3 under air and sunlight without the use of photosesitizer, producing symmetrical and unsymmetrical diaryl, heterodiaryl, and cyclic ketones in good to excellent yields. Moreover, the oxidative cleavage of C-C triple bonds from 1-alkynes is demonstrated for the synthesis of symmetrical and unsymmetrical ketones from the Cu-catalyzed [3+2]-cycloaddition, Rh-catalyzed alkoxyarylation, photooxygenation, and ring-opening reaction in one-pot. Because the synthesis of the symmetrical and unsymmetrical diaryl and/or heterodiaryl ketones bearing an electron-donating group is not easy, the present method is notable.
High-efficiency long-service life organic room-temperature phosphorescence material and preparation method thereof
-
Paragraph 0028; 0029, (2019/01/08)
The invention provides an alkoxy, benzyloxy or bromine substituted xanthone derivative and a preparation method thereof. The xanthone derivative is simple in preparation method, has a phosphorescencepeak on a long wavelength peak and is long in phosphorescence service life and high in light emission efficiency. The preparation method of the xanthone derivative comprises the following preparationsteps: 1, putting phenol, potassium carbonate, DMF (Dimethyl Formamide) and methylbenzene into a reaction container, backflowing for 3-5 hours in a nitrogen environment, and carrying out dehydration treatment till the system has no water generation; removing the methylbenzene, recovering to the room temperature, adding 4-bromine-2-fluorobenzonitrile, backflowing for 3-5 hours in the nitrogen environment, after the reaction is completed, diluting the solution with 100mL of methylbenzene, filtering, washing with water, drying so as to obtain a crude product of a crystal, and purifying with a spectrum column so as to obtain an intermediate as shown in the specification; 2, mixing the intermediate obtained in the step 1 with water and sulfuric acid, heating to 150-200 DEG C in the nitrogen environment, stirring, and backflowing for 10-15 hours; after the reaction is completed, cooling to the room temperature, diluting with water, extracting by using trichloromethane and a saturated sodiumchloride solution, combining organic phases, drying, filtering, carrying out vacuum distillation so as to remove the solvent and obtain a crude product of a crystal, and purifying with a spectrum column, so as to obtain an intermediate as shown in the specification.
Aggregation-induced red light emission material and preparation method thereof
-
Paragraph 0105; 0106, (2017/08/28)
The invention discloses an aggregation-induced red light emission material and a preparation method thereof. The aggregation-induced red light emission material has a general structural formula shown as a formula [I]. When the aggregation-induced red ligh
An efficient combination of Zr-MOF and microwave irradiation in catalytic Lewis acid Friedel-Crafts benzoylation
Doan, Tan L. H.,Dao, Thong Q.,Tran, Hai N.,Tran, Phuong H.,Le, Thach N.
supporting information, p. 7875 - 7880 (2016/05/24)
A zirconium-based metal-organic framework, an effective heterogeneous catalyst, has been developed for the Friedel-Crafts benzoylation of aromatic compounds under microwave irradiation. Constructed by a Zr(iv) cluster and a linker 1,4-bis(2-[4-carboxyphenyl]ethynyl)benzene (H2CPEB), the MOF, possessing large pores and high chemical stability, was appropriate for the enhancement of Lewis acid activity under microwave irradiation. The reaction studies demonstrated that the material could give high yields for a few minutes and maintain its reactivity and structure over several cycles.
Carbonylative Suzuki coupling reactions of aryl iodides with arylboronic acids over Pd/SiC
Cui, Yanli,Guo, Xiaoning,Wang, Yingyong,Guo, Xiangyun
, p. 322 - 327 (2015/09/28)
High surface area SiC has been used to prepare a Pd/SiC catalyst using the liquid reduction method, and the resulting catalyst was used for the carbonylative Suzuki coupling reaction of aryl iodides with arylboronic acids. The catalyst was also characterized by X-ray diffraction, inductively coupled plasma-mass spectroscopy and high-resolution transmission electron microscopy. The results of these analyses showed that homogeneous Pd nanoparticles with a mean diameter of 2.8 nm were uniformly dispersed on the SiC surface. Optimization of the reaction conditions for the carbonylative Suzuki coupling reaction, including the solvent, base, pressure, temperature and reaction time, revealed that the model reaction of iodobenzene (1.0 mmol) with phenylboronic acid (1.5 mmol) could reach 90% conversion with a selectivity of 99% towards the diphenyl ketone using 3 wt% Pd/SiC under 1.0 MPa of CO pressure at 100 °C for 8 h with K2CO3 (3.0 mmol) as the base and anisole as the solvent. The Pd/SiC catalyst exhibited broad substrate scope towards the carbonylative Suzuki coupling reaction of aryl iodides with arylboronic acids bearing a variety of different substituents. Furthermore, the Pd/SiC catalyst exhibited good recyclability properties and could be recovered and reused up to five times with the conversion of iodobenzene decreasing only slightly from 90% to 76%. The decrease in the catalytic activity after five rounds was attributed to the loss of active Pd during the organic reaction.
