830-81-9Relevant articles and documents
Aromatic Carbon-Hydrogen Bond Activation. Novel Synthesis of 1-Naphthol Derivatives by Palladium Catalysed Cyclocarbonylation of Cinnamyl Compounds
Koyasu, Yukio,Matsuzaka, Hiroyuki,Hiroe, Yoshitaka,Uchida, Yasuzo,Hidai, Masanobu
, p. 575 - 576 (1987)
Palladium catalysed cyclocarbonylation of cynnamyl compounds gives 1-naphthol derivatives in good yields whereas the similar carbonylation of trans-β-bromostyrene yields a polymer containing benzindanone units.
Isotopic Fractionation Factor of the Hydrogen-Bonded Complex AcO(1-)...(HOAc)n and Kinetic and Equilibrium Solvent Isotope Effects on Reactions of Acetate Ion in Acetic Acid
Clark, David R.,Emsley, John,Hibbert, Frank
, p. 919 - 922 (1988)
A value of φ 0.58+/-0.05 has been obtained for the deuterium fractionation factor of the hydrogen-bonded complex AcO(1-)...(HOAc)n from (1)H n.m.r. studies of solutions of potassium acetate in AcOH and 97percent AcOD-3percent AcOH.The result is used to account for the kinetic solvent isotope effect 0.66+/-0.10 measured for formation of acetic anhydride from 2,4,6-trinitrophenyl acetate in AcOH and AcOD in the presence of potassium acetate.The equilibrium solvent isotope effect on complex formation between 2,4,6-trinitrophenol and acetate ion in AcOH and 97percent AcOD-3percent AcOH KAcOH/KAcOD 0.83+/-0.1, leads to a value φ ca. 0.7 for the complex (1-).
Method for promoting acylation of amine or alcohol by carbon dioxide
-
Paragraph 0034-0035, (2021/05/29)
The invention relates to a method for promoting acylation of amine or alcohol by carbon dioxide, which comprises the following steps of: mixing an amine compound, carboxylate or thiocarboxylate compound and a reaction solvent under the action of carbon dioxide, and reacting to obtain an amide compound, or under the action of carbon dioxide, mixing the alcohol compound, the thiocarboxylate compound and the reaction solvent [gamma]-valerolactone, and reacting to obtain the ester compound. According to the invention, under the promotion action of carbon dioxide, carboxylate or thiocarboxylate is used as an acylation reagent, and amine and alcohol are converted into amide and ester compounds in the absence of a transition metal catalyst, so that acylation reagents such as acyl chloride or anhydride with irritation and corrosivity are avoided; and the method has the advantages of simple operation, mild reaction conditions, high tolerance of substrate functional groups, strong applicability and high yield, and provides an efficient, reliable and economical preparation method for synthesis of amide and ester compounds.
Direct Acetoxylation of Arenes
Hong Nguyen, Thi Anh,Hou, Duen-Ren
supporting information, p. 8127 - 8131 (2021/08/23)
Acetoxylation of arenes is an important reaction and an unmet need in chemistry. We report a metal-free, direct acetoxylation reaction using sodium nitrate under an anhydrous environment of trifluoroacetic acid, acetic acid, and acetic anhydride. Arenes (31 examples), with oxidation potentials (Eox, in V vs SCE) lower than benzene (2.48 V), were acetoxylated with good yields and regioselectivity. A stepwise, single electron-transfer mechanism is proposed.
Novel naphthyl based 1,2,4-trioxanes: Synthesis and in vivo efficacy in the Plasmodium yoelii nigeriensis in Swiss mice
Hassam, Mohammad,Karnatak, Manvika,Kumar Yadav, Dinesh,Prakash Verma, Ved,Puri, Sunil K.,Rawat, Varun,Sharma, Siddharth,Singh, Chandan,Vanangamudi, Murugesan
, (2021/09/28)
A new series of 1,2,4-trioxanes 9a1-a4, 9b1-b4, 10–13 and 9c1-c4 were synthesized and evaluated against multidrug-resistant Plasmodium yoelii nigeriensis in Swiss mice via oral and intramuscular (i.m.) routes. Adamantane-based trioxane 9b4, the most active compound of the series, provided 100% protection to the infected mice at the dose 48 mg/kg × 4 days and 100% clearance of parasitemia at the dose 24 mg/kg × 4 days via oral route. Adamantane-based trioxane 9b4, is twice active than artemisinin. We have also studied the photooxygenation behaviour of allylic alcohols 6a-b (3-(4-alkoxynaphthyl)-but-2-ene-1-ols) and 6c (3-[4-(tert-butyl-dimethyl-silanyloxy)-naphthalen-1-yl]-but-2-en-1-ol). Being behaving as dienes, they furnished corresponding endoperoxides, while behaving as allylic alcohols, they yielded β-hydroxyhydroperoxides. All the endoperoxides (7a-c) and β-hydroxyhydroperoxides (8a-c) have been separately elaborated to the corresponding 1,2,4-trioxanes, except from endoperoxide 7c. It is worthy to note that TBDMS protected naphthoyl endoperoxide 7c unable to deliver 1,2,4-trioxane, which demonstrated the strength of the O-Si bond is not easy to cleave under acidic condition.
Steric effect of NHC ligands in Pd(II)–NHC-catalyzed non-directed C–H acetoxylation of simple arenes
Mandal, Tanmoy,Yadav, Sudha,Choudhury, Joyanta
, (2021/09/06)
Although there has been a lot of progress in oxidative arene C–H functionalization reactions catalyzed by Pd(II/IV) system, the non-directed, site-selective functionalization of arene molecules is still challenging. It has been established that ligands play a pivotal role in controlling rate- as well as selectivity-determining step in a catalytic cycle involving well-defined metal-ligand bonding. N-heterocyclic carbene (NHC) ligands have had a tremendous contribution in the recent extraordinary success of achieving high reactivity and excellent selectivity in many catalytic processes including cross-coupling and olefin-metathesis reactions. However, the immense potential of these NHC ligands in improving site-selectivity of non-directed catalytic C–H functionalization reactions of simple arenes is yet to be realized, where overriding the electronic bias on deciding selectivity is a burdensome task. The presented work demonstrated an initiative step in this regard. Herein, a series of well-defined discrete [Pd(NHCR′R)(py)I2] complexes with systematically varied degree of spatial congestion at the Pd centre, exerted through the R and R’ substituents on the NHC ligand, were explored in controlling the activity as well as the site-selectivity of non-directed acetoxylation of representative monosubstituted and disubstituted simple arenes (such as toluene, iodobenzene and bromobenzene, naphthalene and 1,2-dichlorobenzene). The resulting best yields were found to be 75% for toluene and 65% for bromobenzene with [Pd(NHCMePh)(py)I2], 75% for iodobenzene and 79% for naphthalene with [Pd(NHCMeMe)(py)I2], and 41% for 1,2-dichlorobenzene with [Pd(NHCCyCy)(py)I2]. Most importantly, with increasing the bulkiness of the NHC ligand in the complexes, the selectivity of the distal C-acetoxylated products in comparison to the proximal ones, was enhanced to a great extent in all cases. Considering the vast library of NHC ligands, this study underscores the future opportunity to develop more strategies to improve the activity and the crucial site-selectivity of C–H functionalization reactions in simple as well as complex organic molecules.
Photo/Thermal Dual Responses in Aqueous-Soluble Copolymers Containing 1-Naphthyl Methacrylate
Zhao, Jiacheng,Er, Gerald Tze Kwang,McCallum, Francis J.,Wang, Sisi,Fu, Changkui,Kaitz, Joshua A.,Cameron, James F.,Trefonas, Peter,Blakey, Idriss,Peng, Hui,Whittaker, Andrew K.
, p. 4860 - 4870 (2021/05/29)
Photoresponsive polymers capable of luminescence switching are attracting significant interest due to their potential application in fluorescence patterning, bioimaging, optical data storage, and anti-counterfeiting. In this work, we have developed aqueous-soluble copolymers of 1-naphthyl methacrylate and oligo(ethylene glycol) methyl ether methacrylate [P(1-NMA-co-OEGMA)] that undergo a significant shift in fluorescence emission wavelength after UV irradiation. Irradiation of the 1-naphthyl methacrylate moieties results in the photo-Fries rearrangement to form hydroxy aryl ketones, which exhibit strong emission at 475 nm through excited-state intramolecular proton transfer (ESIPT) and excited-state proton transfer (ESPT). The resultant shift in fluorescence emission maximum from 338 to 475 nm after rearrangement can potentially be exploited for fluorescence patterning. Furthermore, the copolymers are thermally sensitive in aqueous solutions. The lower critical solution temperature (LCST) of the copolymers depends on the content of hydrophobic 1-naphthyl methacrylate units; the photo-Fries rearrangement results in a more polar structure, shifting the LCST to a higher temperature. Of note, the temperature-triggered volume phase transition of copolymer hydrogels selectively ″switches off″ fluorescence arising from the ESPT mechanism, while the ESIPT emission is unaffected. We also demonstrate that films formed by coating the copolymers onto various substrates can be selectively patterned to form gradients in fluorescence intensity. These versatile P(1-NMA-co-OEGMA) copolymers are simple to prepare at low cost, demonstrate effective photoswitching, and have excellent water solubility, thus ensuring potential applications in a number of important areas.
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.
Copper-Catalyzed Acetylation of Electron-Rich Phenols and Anilines
Zhang, Jieyu,Ke, Qiumin,Tian, Feitao,Jiang, Bei,Ji, Chang-An,Zhang, Lingling,Yu, Jian,Huang, Dayun,Yan, Guobing
supporting information, p. 726 - 730 (2019/03/26)
An approach has been developed for the copper-catalyzed acetylation of phenols and anilines with potassium thioacetate as an acetylating reagent. Although only electron-rich phenols and anilines are compatible with this protocol, the reaction can provide moderate to high yields under mild conditions. Compared with other acetylating reagents, the current reagent has certain advantages, such as its low cost, easy availability, stability, insensitivity to water or air, and ease of storage.
Method for synthesizing phenyl acetate derivatives
-
Paragraph 0021-0026, (2019/05/08)
The invention discloses a method for synthesizing phenyl acetate derivatives. The method of the invention comprises the following steps: 1, adding a phenol derivative, potassium thioacetate, copper acetate and acetonitrile to a reaction tube, and tightening the bottle stopper of the reaction tube, and magnetically stirring at 80 DEG C and reacting for 4 h; and 2, extracting with ethyl acetate, mixing organic phases, removing most of the solvent by reduced pressure distillation, and carrying out column chromatography separation and purification on residual mixed liquor by using petroleum etherand ethyl acetate at the volume ratio of 10:1 as a leacheate so as to obtain a target product. By using a phenol derivative as the raw material and using stable potassium thioacetate, which is cheap and easily available and is easy to operate, as an acetylation reagent, a series of phenyl acetate derivatives are efficiently synthesized, and the yield is considerable.
