5406-33-7Relevant academic research and scientific papers
Synthesis, Characterisation, and Determination of Physical Properties of New Two-Protonic Acid Ionic Liquid and its Catalytic Application in the Esterification
Shahnavaz, Zohreh,Zaharani, Lia,Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie
, p. 165 - 172 (2020/10/26)
A new ionic liquid was synthesised, and its chemical structure was elucidated by FT-IR, 1D NMR, 2D NMR, and mass analyses. Some physical properties, thermal behaviour, and thermal stability of this ionic liquid were investigated. The formation of a two-protonic acid salt namely 4,4′-trimethylene-N,N′-dipiperidinium sulfate instead of 4,4′-trimethylene-N,N′-dipiperidinium hydrogensulfate was evidenced by NMR analyses. The catalytic activity of this ionic liquid was demonstrated in the esterification reaction of n-butanol and glacial acetic acid under different conditions. The desired acetate was obtained in 62-88 % yield without using a Dean-Stark apparatus under optimal conditions of 10 mol-% of the ionic liquid, an alcohol to glacial acetic acid mole ratio of 1.3: 1.0, a temperature of 75-100°C, and a reaction time of 4 h. α-Tocopherol (α-TCP), a highly efficient form of vitamin E, was also treated with glacial acetic acid in the presence of the ionic liquid, and O-acetyl-α-tocopherol (Ac-TCP) was obtained in 88.4 % yield. The separation of esters was conducted during workup without the utilisation of high-cost column chromatography. The residue and ionic liquid were used in subsequent runs after the extraction of desired products. The ionic liquid exhibited high catalytic activity even after five runs with no significant change in its chemical structure and catalytic efficiency.
Trimethylsilyl Esters as Novel Dual-Purpose Protecting Reagents
Chang, Ting-Shuo,Chen, Jyun-Siao,Hsieh, Ya-Chi,Hsu, Hsiao-Lin,Huang, Po-Hsun,Liu, Jen-Wei,Liu, Yu-Hao,Luo, Shun-Yuan,Wu, Hsin-Ru,Wu, Ren-Tsung,Zhang, Kai-Min
supporting information, (2021/12/02)
Trimethylsilyl esters, AcOTMS, BzOTMS, TCAOTMS, etc., are inexpensive and chemically stable reagents that pose a negligible environmental hazard. Such compounds prove to serve as efficient dualpurpose reagents to respectively achieve acylation and trimethylsilylation of alcohols under acidic or basic conditions. Herein, a detailed study on protection of various substrates and new methodological investigations is described.
Synthesis of task-specific imidazolium ionic liquid as an efficient catalyst in acetylation of alcohols, phenols, and amines
Chaubey, Snehkrishn A.,Mishra, Roli
, p. 3259 - 3268 (2020/04/17)
Herein, we report the synthesis of task-specific amino-functionalized imidazolium ionic liquid, acetate1-(2-tert-butoxycarbonylamino-ethyl)-3-methyl-3H-imidazol-1-ium; (Boc-NH-EMIM.OAc), as an efficient catalyst for the acetylation of alcohols, phenols, and amines in the presence of acetic anhydride (acetylating reagent). Remarkably, acetic anhydride in the presence of 10?molpercent of catalyst (Boc-NH-EMIM.OAc) under solvent-free conditions showed excellent acetylation activity in shorter duration of time. On the basis of this, a general procedure for acetylation of alcohols, phenols, and amines has been developed. The ionic liquid (Boc-NH-EMIM.OAc) can be readily recovered and reused successfully up to four consecutive cycles without any significant loss of its catalytic activity. We have been able to show that this acetylating method has many advantages. It gives high yields, takes shorter time, and develops the possibility of benign environmental-friendly process.
KMnO4-catalyzed chemoselective deprotection of acetate and controllable deacetylation-oxidation in one pot
Gurawa, Aakanksha,Kumar, Manoj,Rao, Dodla S.,Kashyap, Sudhir
supporting information, p. 16702 - 16707 (2020/10/27)
A novel and efficient protocol for chemoselective deacetylation under ambient conditions was developed using catalytic KMnO4. The stoichiometric use of KMnO4 highlighted the dual role of a heterogeneous oxidant enabling direct access to aromatic aldehydes in one-pot sequential deacetylation-oxidation. The reaction employed an alternative solvent system and allowed the clean transformation of benzyl acetate to sensitive aldehyde in a single step while preventing over-oxidation to acids. Use of inexpensive and readily accessible KMnO4 as an environmentally benign reagent and the ease of the reaction operation were particularly attractive, and enabled the controlled oxidation and facile cleavage of acetate in a preceding step. This journal is
Rhodium-Catalyzed Reductive Esterification Using Carbon Monoxide as a Reducing Agent
Ostrovskii, Vladimir S.,Runikhina, Sofiya A.,Afanasyev, Oleg I.,Chusov, Denis
supporting information, p. 4116 - 4121 (2020/07/13)
Carbon monoxide used to have a limited number of applications in organic chemistry, but it gradually increases its role as a mild and selective reducing agent. It can be applied for the carbon–heteroatom single bond formation via the reductive addition of hydrogen-containing nucleophiles to carbonyl compounds. In this paper, rhodium-catalyzed reductive esterification is described, and a comparative study of the rhodium and ruthenium catalysis in the reductive addition reactions is provided. Rhodium performs better on highly nucleophilic substrates and ruthenium is better for compounds with less nucleophilicity.
Tris(pyrazolyl)borate rhodium complexes. Application for reductive amination and esterification of aldehydes in the presence of carbon monoxide
Kharitonov, Vladimir B.,Ostrovskii, Vladimir S.,Nelyubina, Yulia V.,Muratov, Dmitry V.,Chusov, Denis,Loginov, Dmitry A.
, (2020/09/09)
The halide complexes TpRhCl2(MeOH) and TpMe2RhI2(CO) (Tp = hydrotris-(pyrazolyl)borate; TpMe2 = hydrotris-(3,5-dimethylpyrazolyl)borate) were synthesized by reactions of RhCl3 with K[Tp] in methanol and TpMe2Rh(CO)2 with iodine, respectively. Reactions of TpMe2RhCl2(MeOH) and TpMe2RhI2(CO) with 1,10-phenanthroline afford the phenanthroline derivatives [TpMe2Rh(phen)X]+ (X = Cl, I). The structures of TpRhCl2(MeOH) and TpRhI2(CO) were determined by X-ray diffraction. Tris(pyrazolyl)borate rhodium complexes effectively catalyze the reductive amination and the reductive esterification of aldehydes in the presence of carbon monoxide.
Bu 4 NI-Catalyzed C-C Bond Cleavage and Oxidative Esteri??cation of Allyl Alcohols with Toluene Derivatives
Chen, Yaoyao,Cui, Yongmei,Jia, Xueshun,Li, Chengliang,Li, Jian,Sun, Mingming
, p. 3667 - 3674 (2019/09/30)
A novel oxidative esterification of 1-arylprop-2-en-1-ols with toluene derivatives catalyzed by tetrabutylammonium iodide (TBAI) is reported. The optimization of the reaction conditions illustrates that each of experiment parameters including the catalyst, solvent, and oxidant is significant for present oxidative functionalization. This metal-free protocol has a broad substrate scope including the halogen groups for further functionalization and enriches the reactivity profile of allyl alcohol and toluene derivatives. In addition, this protocol represents a new transformation of allyl alcohol involving C-C bond cleavage and C-O bond forming.
Fe3O4@PEG core/shell nanoparticles as magnetic nanocatalyst for acetylation of amines and alcohols using ultrasound irradiations under solvent-free conditions
Veisi, Hojat,Nikseresht, Ahmad,Rostami, Afsaneh,Hemmati, Saba
, p. 507 - 520 (2018/10/24)
Abstract: Ultrasound irradiation was used to prepare one-pot Fe3O4@PEG core/shell nanostructure for the first time. The morphology, structure, and physicochemical properties were specified by different analytical techniques including field emission scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray powder diffraction, and vibrating sample magnetometer. For acetylation of phenols, alcohols, and amines, the synthesized Fe3O4@PEG core/shell nanoparticles were used as an efficient heterogeneous and green catalyst with acetic anhydride under sonication applying mild reaction conditions. Different electron-withdrawing and electron-donating substrates indicate a prominent yield of desired products with the merit of reusability of Fe3O4@PEG nanocatalyst and magnetic separation. Graphical Abstract: [Figure not available: see fulltext.].
Acylation of Phenols, Alcohols, Thiols, Amines and Aldehydes Using Sulfonic Acid Functionalized Hyper-Cross-Linked Poly(2-naphthol) as a Solid Acid Catalyst
Kalla, Reddi Mohan Naidu,Reddy, Sirigireddy Sudharsan,Kim, Il
, p. 2696 - 2705 (2019/05/28)
Abstract: The hyper-cross-linked porous poly(2-naphthol) fabricated by the Friedel–Crafts alkylation of 2-naphthol has been functionalized with sulfonic acid to obtain a solid acid catalyst. The catalyst is applied for the protection of phenol, alcohols, thiols, amines and aldehydes with acetic anhydride at room temperature. The catalytic protection using the new solid acid is featured by achieving high yield at neat condition, needing no aqueous work-up and/or chromatographic separation, and showing excellent recycling efficiency, suggesting the potential of this sulfonated porous polymers as a new protection protocol in a wide range of sustainable chemical reactions. Graphical Abstract: [Figure not available: see fulltext.].
4-Imidazol-1-yl-butane-1-sulfonic acid ionic liquid: Synthesis, structural analysis, physical properties and catalytic application as dual solvent-catalyst
Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie,Juan, Joon Ching
, p. 866 - 878 (2019/07/12)
4-Imidazol-1-yl-butane-1-sulfonic acid (ImBu-SO3H) has been successfully synthetized and fully characterized by FT-IR and high-resolution NMR spectroscopy (1H, 13C). The “plausible” alternative structures of ImBu-SO3H were discussed on the basis of its NMR data. The ionic liquid showed interesting dual solvent-catalyst property, which was studied experimentally for the acetylation of a variety of functionalized alcohols, phenols, thiols, amines and α-tocopherol (α-CTP) as the most active form of vitamin E with acetic anhydride and which provided good yields within a short reaction time. ImBu-SO3H was successfully recycled by product extraction with an average recovered yield of 82% for 5 subsequent runs. The catalytic activity of the recycled ImBu-SO3H showed almost no loss even after five consecutive runs.
