203641-30-9Relevant academic research and scientific papers
Oxidation of amines and sulfides catalyzed by an assembled complex of phosphotungstate and non-cross-linked amphiphilic polymer
Yamada, Yoichi M. A.,Tabata, Hidetsugu,Takahashi, Hideyo,Ikegami, Shiro
, p. 2031 - 2034 (2002)
Oxidation of sulfides and amines was performed with an assembled catalyst of phosphotungstate and non-cross-linked amphiphilic polymer. The reactions proceeded with hydrogen peroxide under organic solvent-free conditions. This insoluble catalyst was reused five times with the turnover number up to 500.
Sc(OTf)3-catalyzed [3 + 2]-cycloaddition of nitrones with ynones
He, Chun-Ting,Han, Xiao-Li,Zhang, Yan-Xue,Du, Zhen-Ting,Si, Chang-Mei,Wei, Bang-Guo
supporting information, p. 457 - 466 (2021/01/29)
An efficient approach to access functionalized (2,3-dihydroisoxazol-4-yl) ketones has been developed by reacting nitrones 4 with ynones 7 or terminal ynones 10 in a one-pot fashion. The reaction went through a formal Sc(OTf)3-catalyzed [3 + 2]-cycloaddition process to generate a number of functionalized (2,3-dihydroisoxazol-4-yl) ketones 11aa-11aw, 11ba-11la and 12aa-12ae in moderate to good yields. This journal is
Accessing benzooxadiazepines: Via formal [4 + 3] cycloadditions of aza- o -quinone methides with nitrones
Zheng, Yong-Sheng,Tu, Liang,Gao, Li-Mei,Huang, Rong,Feng, Tao,Sun, Huan,Wang, Wen-Xuan,Li, Zheng-Hui,Liu, Ji-Kai
, p. 2639 - 2642 (2018/04/27)
An unprecedented and efficient [4 + 3] cycloaddition of N-(ortho-chloromethyl)aryl amides with nitrones has been developed. This approach provides easy access to a series of seven-membered benzooxadiazepine derivatives in good to excellent yields (up to 99% yield) under mild reaction conditions.
α,β-Unsaturated Amides as Dipolarophiles: Catalytic Asymmetric exo-Selective 1,3-Dipolar Cycloaddition with Nitrones
Zhang, Ming,Kumagai, Naoya,Shibasaki, Masakatsu
supporting information, p. 12450 - 12455 (2017/09/18)
1,3-Dipolar cycloaddition is a commonly exploited method to access 5-membered chemical entities with a variety of peripheral functionalities and their stereochemical arrangements. Nitrones are isolable 1,3-dipoles that exhibit sufficient reactivity toward electron-deficient olefins in the presence of Lewis acids to deliver highly substituted isoxazolidines. Herein we document that α,β-unsaturated amides, generally regarded as barely reactive in a 1,3-dipolar reaction manifold, were effectively activated using the designed 7-azaindoline auxiliary in an In(OTf)3/bishydroxamic acid catalytic system. The broad substrate scope and clean removal of the 7-azaindoline auxiliary from the product highlight the synthetic utility of the present catalysis.
Kinetics studies of rapid strain-promoted [3+2] cycloadditions of nitrones with bicyclo[6.1.0]nonyne
Mackenzie, Douglas A.,Pezacki, John Paul
, p. 337 - 340 (2014/05/06)
Strain-promoted alkyne-nitrone cycloaddition (SPANC) reactions represent a bioorthogonal labeling strategy that is both very rapid and at the same time efficient and selective. Nitrones provide increased reaction rates as well as greater susceptibility to
Nitrones as dipoles for rapid strain-promoted 1,3-dipolar cycloadditions with cyclooctynes
McKay, Craig S.,Moran, Joseph,Pezacki, John Paul
body text, p. 931 - 933 (2010/06/12)
Strain-promoted cycloadditions of nitrones with cyclooctynes (k2 = 1.5 M-1 s-1 at 25 °C) are up to 25 times more rapid than comparable reactions of azides. The Royal Society of Chemistry 2010.
Solvent-free synthesis of nitrones in a ball-mill
Colacino, Evelina,Nun, Pierrick,Colacino, Francesco Maria,Martinez, Jean,Lamaty, Frédéric
, p. 5569 - 5576 (2008/09/21)
Various C-aryl and C-alkyl-nitrones were synthesized within 0.5-2 h via condensation of an equimolar amount of aldehydes and N-substituted-hydroxylamines under solvent-free conditions in?a ball-mill apparatus. Reactions can be performed without the need of excluding air and moisture and yields the expected products with no need for further purification. The study has been complemented by Differential Scanning Calorimetry (DSC) and solid-state 13C MAS nuclear magnetic resonance experiments. We have also studied the temperature profile during the reaction. A comparative study with the corresponding solvent-free microwave activated reaction showed the superiority of the ball-milling method; 31 examples are described, including the synthesis of the anti-aging agent C-phenyl-N-tert-butyl nitrone (PBN) and one of its analogues C-2-pyridyl-N-tert-butylnitrone (2-PyBN).
Oxidation of allylic alcohols, amines, and sulfides mediated by assembled triphase catalyst of phosphotungstate and non-cross-linked amphiphilic copolymer
Yamada, Yoichi M.A.,Tabata, Hidetsugu,Ichinohe, Masato,Takahashi, Hideyo,Ikegami, Shiro
, p. 4087 - 4096 (2007/10/03)
A novel catalyst PWAA, an assembled complex of phosphotungstic acid (H 3PW12O40) and a non-cross-linked copolymer of N-isopropylacrylamide with an ammonium, was developed. It is an amphiphilic, cross-linked, and supramolecular insoluble complex and showed catalytic activity on oxidation with aqueous hydrogen peroxide. PWAA, used in 2.7×10 -5-2.0×10-3molequiv., catalyzed oxidation of allylic alcohols, amines, and sulfides efficiently. The turnover number (TON) of PWAA reached up to 35,000. PWAA showed a good stability in organic/aqueous media and was reused three to five times.
Platelet glycoprotein IIb/IIIa receptor antagonists derived from isoxazolidines
Confalone, Pat N.,Fuqiang, Jin,Mousa, Shaker A.
, p. 55 - 58 (2007/10/03)
A series of isoxazolidines has been synthesized as mimetics of the RGD sequence and was evaluated as antagonists of the platelet glycoprotein IIb/IIIa receptor. These compounds were shown to be highly potent GPIIb/IIIa antagonists, exhibiting submicromolar potencies.
