22568-07-6Relevant academic research and scientific papers
Chiral 4 and 5 - disubstituted pyrrolidine -2 - ketone compound as well as preparation method and application thereof
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Paragraph 0055-0059, (2021/11/26)
The invention belongs to the technical field of organic synthesis, and particularly relates to chiral 4, 5 - disubstituted pyrrolidine -2 - ketone compounds as well as a preparation method and application thereof. The invention firstly uses nitro substituted alkyl (I) and trans α, β - unsaturated 3 - methyl -4 - nitroisoxazole (II) as raw materials, and the asymmetric Michael addition reaction of chiral superbase catalysis I and II is a key step and is hydrolyzed. Esterification and reduction closes the ring, synthesizing a chiral 3, 4 - disubstituted pyrrolidine -2 - ketone compound, including optically pure fenoxone. The asymmetric Michael addition reaction of chiral superbase catalyst for catalyzing 2 -substituted nitroethane (I) and trans α, β -unsaturated 3 - methyl -4 - nitroisoxazole (II) is used for preparing chiral 4 and 5 -disubstituted pyrroli -2 - ketone, and a strapdown is provided for synthesizing chiral 4 and 5 - disubstituted pyrrolidine -2 - ketone skeleton.
A robust heterogeneous Co-MOF catalyst in azide-alkyne cycloaddition and Friedel-Crafts reactions as well as hydrosilylation of alkynes
Wu, Tai-Xue,Jia, Jun-Song,Luo, Wei,Bian, He-Dong,Tang, Hai-Tao,Pan, Ying-Ming,Huang, Fu-Ping
supporting information, p. 872 - 880 (2021/01/25)
Organic reactions using metal-organic frameworks (MOFs) as catalysts are promising with regard to their environmentally friendly features and potential catalyst recyclability. A robust Co(ii)-MOF {[Co2(l-mac)(4,4-bpt)(H2O)]·3.5H2O}n (1) and its enantiomer {[Co2(d-mac)(4,4-bpt)(H2O)]·3.5H2O}n (2) (l/d-mac = basic forms of l/d-malic acid, 4,4-Hbpt = 3,5-di(pyridin-4-yl)-4H-1,2,4-triazole) have been gram-scale prepared under solvothermal conditions. Structural analysis reveals that mac manages Co(ii) ions to form 1-D chains, which are further extended via 4,4-bpt connectors into a noninterpenetrating 3D framework architecture. It was found that 1 can be as a heterogeneous catalyst for multiple organic reactions, such as azide-alkyne cycloaddition and Friedel-Crafts reactions with good isolated yields and good recycle runs (at least five times without substantial degradation). Additionally, 1 can promote hydrosilylation of alkynes under harsh conditions with moderate yield. This journal is
Catalytic Asymmetric Construction of Tertiary Carbon Centers Featuring an α-Difluoromethyl Group with CF2H-CH2-NH2as the "building Block"
Gao, Fengyun,Guo, Yifei,Sun, Mengmeng,Wang, Yalan,Yang, Changyan,Wang, Yuqiang,Wang, Kairong,Yan, Wenjin
supporting information, p. 2584 - 2589 (2021/04/13)
We report here for the first time a novel difluoromethylated ketimine building block condensed by thioisatin and difluoroethylamine, offering efficient access to a broad range of enantioenriched products bearing difluoroethylamine units (27 examples, ≤98% yield, >99% ee) in the presence of quinine-derived squaramide. Further transformation of the intermediate would generate a variety of versatile functional blocks like α-difluoromethyl amines, β-amino acid, and β-diamine with retention of the enantiomeric excess at the difluoromethyl-bound carbon.
Dipolar HCP materials as alternatives to DMF solvent for azide-based synthesis
Bai, Rongxian,Gao, Feng,Gu, Yanlong,Li, Minghao
supporting information, p. 7499 - 7505 (2021/10/12)
Hypercrosslinked polymers HCP-DMF and HCP-DMF-SO3H containing abundant and flexible DMF moieties were designed and synthesized. Benefitting from the solvation microenvironment provided by the pseudo-DMF moities, the polar HCPs manifested outstanding performances in the conversions of NaN3 to benzylic azides and 1,2,3-triazoles in EtOH (95%), respectively, avoiding the use of risky DMF and improving the separation processes of the products.
Geometrically Selective Denitrative Trifluoromethylthiolation of β-Nitrostyrenes with AgSCF3for (E)-Vinyl Trifluoromethyl Thioethers
Fang, Ge,Hong, Jianquan,Huang, Shuai,Jiang, Chao,Liu, Yang,Zhang, Wei,Zheng, Changge
supporting information, (2020/07/03)
An efficient copper(II)-promoted denitrative trifluoromethylthiolation under mild reaction conditions has been developed for vinyl trifluoromethyl thioethers to construct Cvinyl-SCF3 bonds with stable AgSCF3 as a source of the trifluoromethylthio. This reaction system tolerates a broad range of functional groups to commendably achieve a high product yield and excellent stereoselectivity of E/Z.
A photocatalyst-free photo-induced denitroalkylation of β-nitrostyrenes with 4-alkyl substituted Hantzsch esters at room temperature
Duan, Chunying,Hao, Xinyu,Jin, Kun,Li, Yaming,Wang, Jiaao,Zhang, Rong,Zhang, Siyu
supporting information, (2020/02/18)
A photocatalyst-free stereoselectively photo-induced strategy for the denitroalkylation of β-nitrostyrenes using 4-alkyl substituted Hantzsch esters as the alkyl source under xenon lamp irradiation is developed. The reaction proceeds at room temperature and affords the corresponding products in moderate to excellent yields. The oxidant di-t-butyl peroxide serves as an efficient radical initiator under irradiation of a Xenon lamp, initiating alkyl radicals from the 4-alkyl substituted Hantzsch esters.
Preparation method of beta-trans-nitroolefin
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Paragraph 0072-0075, (2020/06/17)
The invention relates to a preparation method of beta-trans-nitroolefin. The method comprises: sequentially adding an olefin compound, a nitration reagent and a solvent into a reaction container, mixing the substances uniformly, and carrying out constant temperature reaction for 18h under an illumination condition to obtain a reaction solution; and sequentially carrying out drying, concentration and column chromatography treatment on the reaction solution to obtain the beta-trans-nitroolefin compound. The method is simple and practicable, low in cost and high in product yield, can realize large-scale production, and has good industrial application prospects in the aspects of functional organic material, bioactive compound and drug synthesis.
Poly(ethylene glycol) supported metal nitrates as well-organized reagents for hunsdiecker conversion of α,β-unsaturated acids to β-nitrostyrenes under solvent and acid-free conditions
Ramesh,Shylaja,Ramgopal,Rao, A. Sambashiva,Rajanna
, p. 1798 - 1800 (2019/07/17)
Poly(ethylene glycol) (PEG) supported metal nitrates such as ferric nitrate and manganese nitrate were accomplished as well-organized reagents for Hunsdiecker conversion of α,β-unsaturated acids to β-nitrostyrenes under acid-free and solvent free conditions using grindstone technique. However, in the case of unsaturated aliphatic acids, nitro alkene derivatives were obtained as products. PEG-400 was found the best among the other PEGs (PEG-200,300, 400, 600, 3000 and 6000) used in this protocol.
Substrate promiscuity of ortho-naphthoquinone catalyst: Catalytic aerobic amine oxidation protocols to deaminative cross-coupling and n-nitrosation
Kim, Hun Young,Oh, Kyungsoo,Si, Tengda
, p. 9216 - 9221 (2019/10/08)
ortho-Naphthoquinone-based organocatalysts have been identified as versatile aerobic oxidation catalysts. Primary amines were readily cross-coupled with primary nitroalkanes via deaminative pathway to give nitroalkene derivatives in good to excellent yields. Secondary and tertiary amines were inert to ortho-naphthoquinone catalysts; however, secondary nitroalkanes were readily converted by ortho-naphthoquinone catalysts to the corresponding nitrite species that in situ oxidized the amines to the corresponding N-nitroso compounds. Without using harsh oxidants in a stoichiometric amount, the present catalytic aerobic oxidation protocol utilizes the substrate promiscuity feature to provide a facile access to amine oxidation products under mild reaction conditions.
