583-68-6Relevant academic research and scientific papers
Selective Thiocyanation and Aromatic Amination to Achieve Organized Annulation of Enaminone with Thiocyanate
Feng, Xukai,Leng, Xin,Li, Jianli,Li, Yao,Liu, Hua,Liu, Lang,Liu, Ping,She, Mengyao,Zhang, Jun,Zhang, Shengyong,Zheng, Tingting
supporting information, p. 8396 - 8401 (2021/11/17)
A tandem insertion of thiocyanate to enamine was performed for the regioselective synthesis of multisubstituted benzoimidazo[2,1-b]thiazoles. This method was shown to be effective in addressing the issue of isomerization encountered in common strategies. With a change made to the leading group on the aniline fragment of enamine, the reaction achieved different transformations, thus enabling multisubstituted benzo[4,5]imidazo[2,1-b]thiazoles and thiazoles in satisfactory yields.
Ni-NiO heterojunctions: a versatile nanocatalyst for regioselective halogenation and oxidative esterification of aromatics
Bhardwaj, Nivedita,Goel, Bharat,Indra, Arindam,Jain, Shreyans K.,Singh, Ajit Kumar,Tripathi, Nancy
, p. 14177 - 14183 (2021/08/16)
Herein, we report a facile method for the synthesis of Ni-NiO heterojunction nanoparticles, which we utilized for the nuclear halogenation reaction of phenol and substituted phenols usingN-bromosuccinimide (NBS). A remarkablepara-selectivity was achieved for the halogenated products under semi-aqueous conditions. Interestingly, blocking of thepara-position of phenol offeredortho-selective halogenation. In addition, the Ni-NiO nanoparticles catalyzed the oxidative esterification of carbonyl compounds with alcohol, diol or dithiol in the presence of a catalytic amount of NBS. It was observed that the aromatic carbonyls substituted with an electron-donating group favoured nuclear halogenation, whereas an electron-withdrawing group substitution in carbonyl compounds facilitated the oxidation reaction. In addition, the catalyst was magnetically separated and recycled 10 times. The tuned electronic structure at the Ni-NiO heterojunction controlled selectivity and activity as no suchpara-selectivity was observed with commercially available NiO or Ni nanoparticles.
5, 10-dihydroindolo [3, 2-b] indole derivative and synthesis method and application thereof
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Paragraph 0051; 0053-0054, (2021/07/17)
The invention discloses a synthesis method of a 5, 10-dihydroindolo [3, 2-b] indole derivative, the method comprises the following steps: mixing a 2-((2-halogen phenyl) ethynyl)-N, N-dimethylaniline derivative (II), N, N-di-tert-butyl diazacycloketone (III), a palladium catalyst, a monophosphine ligand, alkali and a first organic solvent, and carrying out a diamidation reaction under the protection of inert gas to realize the synthesis of the 5, 10-dihydroindolo [3, 2-b] indole derivative(I). The method is easy to operate, mild in reaction condition and high in reaction yield, and the synthesized 5, 10-dihydroindolo [3, 2-b] indole derivative can be used for preparing an organic light-emitting device.
A metal-free aerobic oxidative bromination of anilines and aryl ketones with 2-methylpyridinium nitrate as a reusable ionic liquid
Li, Ming-Fang,Wang, Jian,Ke, Yong-Xin,Pan, Song-Cheng,Yin, Hong,Du, Wenting,Li, Jing-Hua
, p. 267 - 270 (2020/01/08)
An aerobic oxidative bromination of anilines and aryl ketones catalyzed by recyclable 2-methylpyridinium nitrate ionic liquid is achieved in water using hydrobromic acid as the bromine source and molecular oxygen as the oxidant. The catalytic system shows good efficiency and atom economy.
Nitromethane as a reagent for the synthesis of 3-nitroindoles from 2-haloarylamine derivatives
Chesnokov,Ageshina,Maryanova,Rzhevskiy,Gribanov,Topchiy,Nechaev,Asachenko
, p. 2370 - 2377 (2020/12/31)
A new approach to the synthesis of 3-nitroindoles using palladium-catalyzed arylation of nitromethane with N-(2-bromoaryl)imidates was developed. A convenient and rapid method for cyclization of ethyl N-(2-nitromethylaryl)acetimidates to 2-methyl-3-nitro-1H-indoles was proposed.
Making endo-cyclizations favorable again: A conceptually new synthetic approach to benzotriazoles via azide group directed lithiation/cyclization of 2-azidoaryl bromides
Ageshina, Alexandra A.,Chesnokov, Gleb A.,Topchiy, Maxim A.,Alabugin, Igor V.,Nechaev, Mikhail S.,Asachenko, Andrey F.
supporting information, p. 4523 - 4534 (2019/05/17)
Although benzotriazoles are important and ubiquitous, currently there is only one conceptual approach to their synthesis: bridging the two ortho-amino groups with an electrophilic nitrogen atom. Herein, we disclose a new practical alternative-the endo-cyclization of 2-azidoaryl lithiums obtained in situ from 2-azido-aryl bromides. The scope of the reaction is illustrated using twenty-four examples with a variety of alkyl, alkoxy, perfluoroalkyl, and halogen substituents. We found that the directing effect of the azide group allows selective metal-halogen exchange in aryl azides containing several bromine atoms. Furthermore, (2-bromophenyl)diazomethane undergoes similar cyclization to give an indazole. Thus, cyclizations of aryl lithiums containing an ortho-X = Y = Z group emerge as a new general approach for the synthesis of aromatic heterocycles. DFT computations suggested that the observed endo-selectivity applies to the anionic cyclizations of other functionalities that undergo "1,1-additions" (i.e., azides, diazo compounds, and isonitriles). In contrast, cyclizations with the heteroatomic functionalities that follow the "1,2-addition" pattern (cyanates, thiocyanates, isocyanates, isothiocyanates, and nitriles) prefer the exo-cyclization path. Hence, such reactions expand the current understanding of stereoelectronic factors in anionic cyclizations.
Sodium sulfate-hydrogen peroxide-sodium chloride adduct: selective protocol for the oxidative bromination, iodination and temperature dependent oxidation of sulfides to sulfoxides and sulfones
Gayakwad, Eknath M.,Patel, Khushbu P.,Shankarling, Ganapati S.
supporting information, p. 6001 - 6009 (2019/04/17)
The regioselective bromination and iodination of unprotected aromatic primary amines using enclathrated hydrogen peroxide as an oxidant under mild conditions has been developed, in which potassium bromide (KBr) and potassium iodide (KI) were used as brominating and iodinating agents, respectively. The adduct shows not only regioselectivity for para- or ortho-isomers but also a remarkable chemoselectivity for monobromination. Selective oxidation of sulfides to sulfoxides and sulfones has also been studied and good to excellent yields of the desired products were obtained. Acetic acid was found to be the solvent of choice for these reactions. This simple method represents an ecologically benign and alternative pathway for the oxidative halogenation of anilines and the oxidation of sulfides to sulfoxides and sulfones.
Regulating Transition-Metal Catalysis through Interference by Short RNAs
Green, Sydnee A.,Montgomery, Hayden R.,Benton, Tyler R.,Chan, Neil J.,Nelson, Hosea M.
supporting information, p. 16400 - 16404 (2019/08/26)
Herein we report the discovery of a AuI–DNA hybrid catalyst that is compatible with biological media and whose reactivity can be regulated by small complementary nucleic acid sequences. The development of this catalytic system was enabled by the discovery of a novel AuI-mediated base pair. We found that AuI binds DNA containing C-T mismatches. In the AuI–DNA catalyst's latent state, the AuI ion is sequestered by the mismatch such that it is coordinatively saturated, rendering it catalytically inactive. Upon addition of an RNA or DNA strand that is complementary to the latent catalyst's oligonucleotide backbone, catalytic activity is induced, leading to a sevenfold increase in the formation of a fluorescent product, forged through a AuI-catalyzed hydroamination reaction. Further development of this catalytic system will expand not only the chemical space available to synthetic biological systems but also allow for temporal and spatial control of transition-metal catalysis through gene transcription.
o-xylylene bis(triethyl ammonium tribromide) as a mild and recyclable reagent for rapid and regioselective bromination of anilines and phenols
Hemati, Roya,Shahvelayati, Ashraf S.,Yadollahzadeh, Khadijeh
, p. 682 - 687 (2018/07/14)
Background: o-Xylylene bis(triethyl ammonium tribromide) (OXBTEATB) as a recyclable and high bromine containing di-(tribromide) reagent has been employed for the bromination of various organic substrates such as phenol and aniline or its derivatives. This catalyst can be recovered and reused several times. Methods: Aryl bromides shown in Table 1, were easily produced from bromination of aromatic compounds by OXBTEATB. This high-yield process lets the reagents to be recycled and reused. Results: As shown in Table 1, substituted anilines, phenols and β-naphthol were found to be the most reactive and immediately converted to the corresponding mono-brominated products by OXBTEATB. Conclusion: OXBTEATB can be considered a solidified bromine. This novel reagent has variable solubility in different polar protic and aprotic solvents but insoluble in non-polar aprotic solvent. Subsequently, OXBTEATB can be recognized as a more useful brominating and regioselective catalyst than the liquid bromine.
Direct Synthesis of Structurally Divergent Indole Alkaloids from Simple Chemicals
Shen, Tao,Zhu, Bencong,Lin, Fengguirong,Pan, Jun,Wei, Jialiang,Luo, Xiao,Liu, Jianzhong,Jiao, Ning
supporting information, p. 815 - 818 (2018/07/31)
A direct and structurally divergent synthesis of indole alkaloids from very simple 2-vinylanilines, alkynes and TBN via a novel substrate fragmentation/cycloaddition strategy has been developed, which provides an efficient noble-metal-free approach to access a library of highly valuable indole derivatives of tryptamines and tryptamine-related oximes, lactams, and lactones, as well as β-carbolines, spiroindolines, and hexa-hydropyrrolo[2,3-b]indoles.
