27153-17-9Relevant academic research and scientific papers
Copper-Catalyzed Cascade N-Dealkylation/N-Methyl Oxidation of Aromatic Amines by Using TEMPO and Oxygen as Oxidants
Li, Dianjun,Wang, Shihaozhi,Yang, Jiale,Yang, Jinhui
supporting information, p. 6768 - 6772 (2021/12/31)
A novel tandem N-dealkylation and N-methyl aerobic oxidation of tertiary aromatic amines to N-arylformamides using copper and TEMPO has been developed. This methodology suggested an alternative synthetic route from N-methylarylamines to N-arylformamides.
Acid-catalyzed chemodivergent reactions of 2,2-dimethoxyacetaldehyde and anilines
Guo, Luxia,Chen, Zihao,Zhu, Hongmei,Li, Minghao,Gu, Yanlong
supporting information, p. 1419 - 1422 (2020/11/12)
Chemodivergent reactions of 2,2-dimethoxyacetaldehyde and anilines were described, which were established on the basis of either a C[sbnd]C bond cleavage or a rearrangement process of a reaction intermediate. These reactions proceeded in a condition-determined manner with good functional group tolerance. In the first model, 2,2-dimethoxyacetaldehyde reacted with aniline to form a new C[sbnd]N bond, in the presence of O2, via a C[sbnd]C bond cleavage reaction. However, in the second model, by performing the reaction in the absence of O2, Heyns rearrangement occurred and generated a new C[sbnd]O bond to form methyl phenylglycinate. Such condition-determined reactions not only offered the new way for value-added conversion of biomass-derived platform molecule, 2, 2-dimethoxyacetaldehyde, but also provided efficient methods for the synthesis of N-arylformamides and methyl phenylglycinates.
Selective: N-formylation/N-methylation of amines and N-formylation of amides and carbamates with carbon dioxide and hydrosilanes: Promotion of the basic counter anions of the zinc catalyst
Zhang, Qiao,Lin, Xiao-Tao,Fukaya, Norihisa,Fujitani, Tadahiro,Sato, Kazuhiko,Choi, Jun-Chul
supporting information, p. 8414 - 8422 (2020/12/29)
A catalyst composed of commercially available Zn(OAc)2 and 1,10-phenanthroline (phen) was effective in the N-formylation/N-methylation of amines using CO2 as the C1 source in the presence of hydrosilanes. An equimolar reaction of N-methylaniline with PhSiH3 under a CO2 atmosphere yielded the N-formylation product in 92% yield at 25 °C. Scale-up of the reaction using 10 mmol substrate was also successful in affording the desired product in 83% yield (1.1 g). This catalyst exhibits a high thermal stability and a turnover number (TON) of 385000 at 150 °C. In addition, the reaction of N-methylaniline in the presence of excess Ph2SiH2 produced N,N-dimethylaniline. Furthermore, our catalytic protocol was developed for the N-formylation of amides and carbamates, which have smaller pKa values and lower reactivities than the corresponding amines. The present Zn(OAc)2/phen catalyst was found to show versatility in the conversion of CO2 and amines into several functionalized organic chemicals under mild conditions. We propose that the basic counter anion (i.e., the acetate) of the catalyst activates both the Si-H and N-H bonds.
UiO-66 as an efficient catalyst for N-formylation of amines with CO2 and dimethylamine borane as a reducing agent
Phatake, Vishal V.,Mishra, Ashish A.,Bhanage, Bhalchandra M.
supporting information, (2019/12/11)
The most effective way to make the best use of CO2, is the reductive formylation of amines, as formamides have many applications in industry. A new protocol has been developed for reductive N-formylation of amines with CO2 as a C1 carbon source and DMAB (Dimethylamine borane) as a reducing agent in the presence of Zr-containing metal–organic framework (MOF) as an efficient, heterogeneous recyclable catalyst. We used UiO-66 and UiO-66-NH2 as catalysts for N-formylation of amines and observed that both the catalyst performs equally. Therefore, we continued our studies with UiO-66 as a catalyst. The UiO-66 MOF shows good catalytic activity and affording the desired formamides in good to excellent yield. This catalytic system is very efficient for several amines including primary and secondary aliphatic cyclic and aromatic amines. Moreover, the prepared catalyst was recycled up to four recycled without a considerable decrease in catalytic activity.
L-Serine?ZnO as an efficient and reusable catalyst for synthesis of cyclic carbonates and formamides in presence of CO2 atmosphere
Ahire, Jayendra P.,Bhanage, Bhalchandra M.,Phatake, Vishal V.
, (2020/06/03)
The highly efficient carbon dioxide (CO2) fixation into value-added organic carbonates has gained enormous attention in the last few decades. This work reports, synthesis and characterization of amino acids (AAs) assisted ZnO nano catalyst and Its application for the cyclic carbonates and formamides synthesis with CO2 atmosphere. The prepared catalysts are characterized by IR, SEM, TEM, XRD, DSC-TGA XPS analysis. L-Serine?ZnO exhibits excellent catalytic activity for transformation of CO2 into value-added chemicals namely formamides and cyclic carbonates. The catalytic systems which work in the presence of CO2 balloon atmosphere for the synthesis of cyclic carbonates are rarely explored. This catalytic system shows excellent activity under the CO2 balloon atmosphere for carbonate synthesis. The developed methodology demonstrates broad substrate scope as well as excellent functional group tolerance for carbonates and formamides synthesis. Additionally, the synthesized catalyst was recyclable up to five recycling runs without considerable loss in its catalytic activity, thus makes this protocol cost-effective and sustainable.
Tetracoordinate borates as catalysts for reductive formylation of amines with carbon dioxide
Du, Chen-Xia,Huang, Zijun,Jiang, Xiaolin,Li, Yuehui,Makha, Mohamed,Wang, Fang,Zhao, Dongmei
supporting information, p. 5317 - 5324 (2020/09/17)
We report sodium trihydroxyaryl borates as the first robust tetracoordinate organoboron catalysts for reductive functionalization of CO2. These catalysts, easily synthesized from condensing boronic acids with metal hydroxides, activate main group element-hydrogen (E-H) bonds efficiently. In contrast to BX3 type boranes, boronic acids and metal-BAr4 salts, under transition metal-free conditions, sodium trihydroxyaryl borates exhibit high reactivity of reductive N-formylation toward a variety of amines (106 examples), including those with functional groups such as ester, olefin, hydroxyl, cyano, nitro, halogen, MeS-, ether groups, etc. The over-performance to catalyze formylation of challenging pyridyl amines affords a promising alternative method to the use of traditional formylation reagents. Mechanistic investigation supports electrostatic interactions as the key for Si/B-H activation, enabling alkali metal borates as versatile catalysts for hydroborylation, hydrosilylation, and reductive formylation/methylation of CO2.
Novel 1,3,4-Selenadiazole-Containing Kidney-Type Glutaminase Inhibitors Showed Improved Cellular Uptake and Antitumor Activity
Chen, Zhao,Li, Di,Xu, Ning,Fang, Jinzhang,Yu, Yan,Hou, Wei,Ruan, Haoqiang,Zhu, Panpan,Ma, Renchao,Lu, Shiying,Cao, Danhui,Wu, Rui,Ni, Mowei,Zhang, Wei,Su, Weike,Ruan, Benfang Helen
supporting information, p. 589 - 603 (2019/01/10)
Kidney-type glutaminase [KGA/isoenzyme glutaminase C (GAC)] is becoming an important tumor metabolism target in cancer chemotherapy. Its allosteric inhibitor, CB839, showed early promise in cancer therapeutics but limited efficacy in in vivo cancer models. To improve the in vivo activity, we explored a bioisostere replacement of the sulfur atom in bis-2-(5-phenylacetamido-1,2,4-thiadiazol)ethyl sulfide and CB839 analogues with selenium using a novel synthesis of the selenadiazole moiety from carboxylic acids or nitriles. The resulting selenadiazole compounds showed enhanced KGA inhibition, more potent induction of reactive oxygen species, improved inhibition of cancer cells, and higher cellular and tumor accumulation than the corresponding sulfur-containing molecules. However, both CB839 and its selenium analogues show incomplete inhibition of the tested cancer cells, and a partial reduction in tumor size was observed in both the glutamine-dependent HCT116 and aggressive H22 liver cancer xenograft models. Despite this, tumor tissue damage and prolonged survival were observed in animals treated with the selenium analogue of CB839.
Palladium-Catalyzed Diarylation of Isocyanides with Tetraarylleads for the Selective Synthesis of Imines and α-Diimines
Tran, Cong Chi,Kawaguchi, Shin-Ichi,Kobiki, Yohsuke,Matsubara, Hitomi,Tran, Dat Phuc,Kodama, Shintaro,Nomoto, Akihiro,Ogawa, Akiya
, p. 11741 - 11751 (2019/10/02)
Using tetraaryllead compounds (PbAr4) as arylating reagents, isocyanides undergo selective diarylation in the presence of palladium catalysts such as Pd(OAc)2 or Pd(PPh3)4 to afford imines and/or α-diimines based on the isocyanide employed. With aliphatic isocyanides, imines are obtained preferentially, whereas α-diimines are formed in the case of electron-rich aromatic isocyanides. The differences in imine/α-diimine selectivity can be attributed to the stability of imidoylpalladium intermediates formed in this catalytic reaction. Compared with other arylating reagents, tetraaryllead compounds are excellent candidates for use in the selective transformations to imines and/or α-diimines, especially in terms of inhibiting the oligomerization of isocyanides, which results in a lower product selectivity in many transition-metal-catalyzed reactions of isocyanides.
Visible-light-induced radical cascade cyclization of oxime esters and aryl isonitriles: Synthesis of cyclopenta[: B] quinoxalines
Yuan, Yao,Dong, Wu-Heng,Gao, Xiao-Shuang,Xie, Xiao-Min,Zhang, Zhao-Guo
supporting information, p. 11900 - 11903 (2019/10/11)
A visible-light-induced radical cascade cyclization of aryl isonitriles and cyclobutanone oxime esters for the synthesis of cyclopenta[b]quinoxalines has been accomplished for the first time. The key to the success of this process was the integration of the in situ-formed nitrile radical followed by the cascade radical isonitrile/nitrile insertion-cyclization. The easy introduction of substituents for both substrates and the high functional group tolerance of the reaction make it an efficient strategy to give various quinoxaline derivatives in moderate to good yields.
Cu@U-g-C3N4 Catalyzed Cyclization of o-Phenylenediamines for the Synthesis of Benzimidazoles by Using CO2 and Dimethylamine Borane as a Hydrogen Source
Phatake, Vishal V.,Bhanage, Bhalchandra M.
, p. 347 - 359 (2018/11/23)
Abstract: This work reports a green and sustainable route for the synthesis of benzimidazoles via C–N bond formation using carbon dioxide (CO2) as a C1 carbon source. In this work, Cu@U-g-C3N4 catalyst was prepared from urea derived porous graphitic carbon?nitride (U-g-C3N4) and CuCl2 and characterized by FT-IR, XRD, XPS, SEM, TPD etc. The Cu@U-g-C3N4 as a heterogeneous recyclable catalyst has been employed first time for the cyclization of o-phenylenediamines (OPD) with CO2 to benzimidazoles using dimethylamine borane (DMAB). The proposed protocol becomes sustainable and efficient due to the use of propylene carbonate/water as a suitable biodegradable, economical and environmentally benign solvent system. The proposed catalytic system showed a wide range of substrate scope for the synthesis of benzimidazoles in good to excellent yields. Graphical Abstract: [Figure not available: see fulltext.]
