3638-64-0Relevant academic research and scientific papers
Organocatalytic Enantioselective Michael-Aldol[3+2] Annulation for the Synthesis of Nitro-Methanobenzo[7] annulenes
Liu, Jin-Yu,Zhang, Xiao-Hai,Zhang, Yang
supporting information, p. 5008 - 5011 (2021/09/28)
We report an enantioselective Michael-Aldol[3+2] annulation between 2-alkyl-3-hydroxynaphthalene-1,4-diones and nitroalkenes using a bifunctional thiourea catalyst, and a series of nitro-methanobenzo[7]annulenes with potential biological activities were synthesized in good yields with excellent enantio- and diastereoselectivities. A gram-scale synthesis and further transformation of the product demonstrated the synthetic value of this reaction.
Enantioselective catalytic approach to the C23–C28 subunit of 24α-methyl steroids
Yakimchyk, Viktoryia S.,Kazlova, Volha V.,Hurski, Alaksiej L.,Savchenko, Rimma G.,Kostyleva, Svetlana A.,Zhabinskii, Vladimir N.,Khripach, Vladimir A.
supporting information, p. 82 - 90 (2019/05/24)
Enantioselective synthesis of C23–C28 subunit of campestane steroids based on catalytic methods is reported. The synthesis was started from (S)-2-isopropyl-4-nitrobutan-1-ol, which is easily accessible by the reaction between isovaleraldehyde and nitroethylene catalyzed by only 2% of (S)-trimethylsilyldiphenylprolinol. Removal of one “extra” carbon from the nitroalcohol was achieved by Ni-catalyzed hydrodecarboxylation of the redox-active ester intermediate. The synthesized C23–C28 fragment was attached to a steroidal core by Julia-Kocienski reaction of a steroidal aldehyde with metallated C23–C28 sulfone. The obtained product of olefination was easily transformed to a precursor of campesterol and (Z)-22-dehydrocampesterol.
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.
Synthesis of nitroolefins and nitroarenes under mild conditions
Zarei, Mahmoud,Noroozizadeh, Ehsan,Moosavi-Zare, Ahmad R.,Zolfigol, Mohammad A.
, p. 3645 - 3650 (2018/04/14)
1,3-Disulfonic acid imidazolium nitrate {[Dsim]NO3} was prepared and characterized as a new ionic liquid and nitrating agent for the ipso-nitration of various arylboronic acids and nitro-Hunsdiecker reaction of different α,β-unsaturated acids and benzoic acid derivatives, by in situ generation of NO2 to give various nitroarenes and nitroolefins without using any cocatalysts and solvents under mild conditions.
HERBICIDAL COMPOUNDS
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Page/Page column 90, (2016/05/24)
The present invention relates to a compound of formula (I) wherein: wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11 and G are as defined herein; and wherein the compound of formula (I) is optionally present as an agrochemically acceptable salt thereof. These compounds are thought to be suitable for use as herbicides. The invention therefore also relates to a method of controlling weeds, especially grassy monocotyledonous weeds, in crops of useful plants, comprising applying a compound of formula (I), or a herbicidal composition comprising such a compound, to the plants or to the locus thereof.
Zeolite Y-assisted nitration of aromatic and heterocyclic compounds and decarboxylative nitration of α,β-unsaturated acids under non-conventional conditions
Sudhakar Chary,Rajanna,Krishnaiah,Srinivas
, p. 1430 - 1434 (2016/03/08)
Zeolite Y was found to be an efficient catalyst for a facile nitration of aromatic compounds with acetonitrile as the solvent in the presence of small amounts of HNO3 at room temperature. The reactions afforded mono-nitro derivatives of aromatic compounds in about three hours under stirred conditions with high yields and regioselectivity. The reaction times drastically reduced to about 20 min under sonication and to about 20 s under microwave irradiation. Zeolite is recovered after completion of the reaction and recycled for three to four times without any problem. The approach is particularly appropriate for the conversion of unsaturated cinnamic acids into nitrostyrenes.
Asymmetric dearomatization of β-naphthols through a bifunctional-thiourea-catalyzed michael reaction
Wang, Shou-Guo,Liu, Xi-Jia,Zhao, Qun-Chao,Zheng, Chao,Wang, Shao-Bo,You, Shu-Li
supporting information, p. 14929 - 14932 (2016/02/05)
An intermolecular asymmetric dearomatization reaction of β-naphthols with nitroethylene through a chiral-thiourea-catalyzed Michael reaction is described. Enantioenriched functionalized β-naphthalenones with an all-carbon quaternary stereogenic center could thus be easily constructed from simple naphthol derivatives in good yields and excellent enantioselectivity (up to 79 % yield, 98 % ee). An intermolecular asymmetric dearomatization reaction of β-naphthols with nitroethylene through a chiral-thiourea-catalyzed Michael reaction is described. Enantioenriched functionalized β-naphthalenones with an all-carbon quaternary stereogenic center were easily constructed in good yields and excellent enantioselectivity (up to 79 % yield, 98 % ee).
Metal-free ring expansion of indoles with nitroalkenes: A simple, modular approach to 3-substituted 2-quinolones
Aksenov, Alexander V.,Smirnov, Alexander N.,Aksenov, Nicolai A.,Aksenova, Inna V.,Matheny, Jonathon P.,Rubin, Michael
, p. 8647 - 8656 (2015/03/03)
3-Substituted 2-quinolones are obtained via a novel metal-free transannulation reaction of 2-nitroolefins with 2-substituted indoles in polyphosphoric acid. This acid-mediated cascade transformation operates via the ANRORC (Addition of Nucleophile, Ring Opening, and Ring Closure) mechanism and can be used in combination with the Fisher indole synthesis to offer a practical three-component hetero-annulation approach to 2-quinolones from arylhydrazines, 2-nitroalkenes, and acetophenone. An alternative entry to this chemistry employing the alkylation of electron-rich arenes and hetarenes with 1-(2-indolyl)-2-nitroalkene has also been demonstrated.
Catalytic Asymmetric Reactions of 4-Substituted Indoles with Nitroethene: A Direct Entry to Ergot Alkaloid Structures
Romanini, Simone,Galletti, Emilio,Caruana, Lorenzo,Mazzanti, Andrea,Himo, Fahmi,Santoro, Stefano,Fochi, Mariafrancesca,Bernardi, Luca
supporting information, p. 17578 - 17582 (2015/12/05)
A domino Friedel-Crafts/nitro-Michael reaction between 4-substituted indoles and nitroethene is presented. The reaction is catalyzed by BINOL-derived phosphoric acid catalysts, and delivers the corresponding 3,4-ring-fused indoles with very good results in terms of yields and diastereo- and enantioselectivities. The tricyclic benzo[cd]indole products bear a nitro group at the right position to serve as precursors of ergot alkaloids, as demonstrated by the formal synthesis of 6,7-secoagroclavine from one of the adducts. DFT calculations suggest that the outcome of the reaction stems from the preferential evolution of a key nitronic acid intermediate through a nucleophilic addition pathway, rather than to the expected "quenching" through protonation.
Ultrasonically Assisted Rate Enhancements in Trichloroisocyanuric Acid/DMF/NaNO2 Triggered Nitration of Aromatic Compounds and Decarboxylative Nitration of α,β-Unsaturated Acids
Kumar, Mukka Satish,Rajanna, Kamatala Chinna,Venkateswarlu, Marri,Venkanna, Purugula,Saiprakash, Pondichery Kuppuswamy
, p. 2251 - 2258 (2015/09/22)
An efficient and safe method for nitration of aromatic compounds and decarboxylative nitration of α,β-unsaturated acids was developed using trichloroisocyanuric acid (TCICA)/dimethylformamide (DMF) in the presence of NaNO2. The reaction times of conventional protocol reduced from 8-10 h to 1.0-1.5 h (60-90 min) under sonication, even though the yields are comparable under both the conditions.
