217433-67-5Relevant articles and documents
Asymmetric Epoxidation of Enones Promoted by Dinuclear Magnesium Catalyst
Jaszczewska-Adamczak, Joanna A.,Mlynarski, Jacek
supporting information, p. 4247 - 4255 (2021/07/17)
Asymmetric synthesis with cheaper and non-toxic alkaline earth metal catalysts is becoming an important and sustainable alternative to conventional catalytic methodologies mostly relying on precious metals. In spite of some sustainable methods for enantioselective epoxidation of enones, the development of a well-defined and efficient catalyst based on magnesium complexes for these reactions is still a challenging task. In this perspective, we present the application of chiral dinuclear magnesium complexes for asymmetric epoxidation of a broad range of electron-deficient enones. We demonstrate that the in situ generated magnesium-ProPhenol complex affords enantioenriched oxiranes in high yields and with excellent enantioselectivities (up to 99% ee). Our extensive study verifies the literature data in this area and provides a step forward to better understand the factors controlling the oxygenation process. Elaborated catalyst offers mild reaction conditions and a truly wide substrate scope. (Figure presented.).
Efficient generation of hydrogen peroxide by aerobic photooxidation of 2-propanol using anthraquinone-2-carboxylic acid and one-pot epoxidation of α,β-unsaturated ketones
Cui, Lei,Furuhashi, Sohei,Tachikawa, Yuma,Tada, Norihiro,Miura, Tsuyoshi,Itoh, Akichika
, p. 162 - 165 (2013/02/21)
We developed an efficient method for the generation of hydrogen peroxide by aerobic photooxidation of 2-propanol using anthraquinone-2-carboxylic acid and molecular oxygen in air and visible light from fluorescent lamps. One-pot epoxidation of α,β-unsaturated ketones using the generated hydrogen peroxide is also reported.
Facial selectivity and stereospecificity in the (4 + 3) cycloaddition of epoxy enol silanes
Lo, Brian,Chiu, Pauline
supporting information; experimental part, p. 864 - 867 (2011/05/06)
The scope of the (4 + 3) cycloaddition using epoxy enol silanes has been examined. Unhindered and nucleophilic dienes react to give the highest yields, but hindered dienes give rise to higher diastereoselectivities. Notably, the cycloaddition shows facial
Highly enantioselective epoxidation of α,β-unsaturated ketones catalyzed by primary-secondary diamines
Lu, Yingpeng,Zheng, Changwu,Yang, Yingquan,Zhao, Gang,Zou, Gang
supporting information; experimental part, p. 3129 - 3133 (2012/01/03)
The asymmetric epoxidation of α,β-unsaturated ketones has been achieved by using functional and readily accessible primary-secondary diamines as the catalysts, giving the useful alkyl epoxy products with good yields and high enantioselectivities (up to 99% ee). Copyright
Amino-acid-mediated epoxidation of α,β-unsaturated ketones by hydrogen peroxide in aqueous media
Kim, Juhyun,Jung, Suhyun,Park, Seongsoon,Park, Sojung
experimental part, p. 2866 - 2868 (2011/06/21)
Amino acids, such as arginine and lysine, can be used as an efficient catalyst in the epoxidation of α,β-unsaturated ketones with aqueous hydrogen peroxide. Up to >99% conversion was obtained in the reaction toward 11 α,β-unsaturated ketones.
Asymmetric oxidations of electron-poor alkenes promoted by the β-amino alcohol/TBHP system
Russo, Alessio,Lattanzi, Alessandra
experimental part, p. 1551 - 1556 (2009/12/06)
The asymmetric oxyfunctionalization of alkenes is a fundamental process in synthetic organic chemistry. In this contribution, we review our findings on the enantioselective organocatalyzed oxidation of electron-poor alkenes. Readily or commercially available β-amino alcohols displayed catalytic activity in the asymmetric epoxidation of α,β-enones and β-peroxidation of nitroalkenes with tert-butyl hydroperoxide (TBHP) as the oxidant. The corresponding epoxides and peroxides were isolated in good to high yield and enantioselectivity. Georg Thieme Verlag Stuttgart.
Catalytic enantioselective peroxidation of α,β-unsaturated ketones
Lu, Xiaojie,Liu, Yan,Sun, Bingfeng,Cindric, Brittany,Deng, Li
supporting information; body text, p. 8134 - 8135 (2009/02/02)
Despite the potential of chiral peroxides as biologically interesting or even clinically important compounds, no catalytic enantioselective peroxidation has been reported. With a chiral catalyst not only to induce enantioselectivity but also to convert a well established epoxidation pathway into a peroxidation pathway, the first efficient catalytic peroxidation has been successfully developed. Employing readily available α,β-unsaturated ketones and hydroperoxides and an easily accessible cinchona alkaloid catalyst, this novel reaction will open new possibilities in the asymmetric synthesis of chiral peroxides. Under different conditions a highly enantioselective epoxidation with the same starting materials, reagents, and catalyst has was also established. Copyright
4-Substituted-α,α-diaryl-prolinols improve the enantioselective catalytic epoxidation of α,β-enones
Li, Yawen,Liu, Xinyuan,Yang, Yingquan,Zhao, Gang
, p. 288 - 291 (2007/10/03)
To seek novel metal-free organic catalysts for epoxidation with high stereoselectivity, a series of 4-substituted-α,α-diaryl-prolinols were synthesized in four steps from trans-4-hydroxyl-L-proline. These prolinol derivatives catalyzed the asymmetric epoxidation of α,β-enones to give the corresponding chiral epoxides in good yields and high enantioselectivities under mild reaction conditions. Studies of substituent effects on enantioselectivity revealed that steric bulk and electronic effect promoted higher enantioselectivity, and prolinol 8a was found to be the best catalyst until now.
Bis(3,5-dimethylphenyl)-(S)-pyrrolidin-2-ylmethanol: An improved organocatalyst for the asymmetric epoxidation of α,β-enones
Lattanzi, Alessandra
, p. 339 - 346 (2007/10/03)
The asymmetric epoxidation of α,β-enones by the readily available bis(3,5-dimethylphenyl)-(S)-pyrrolidin-2-ylmethanol and tert-butyl hydroperoxide (TBHP) is described. Stereoelectronic substitution on the aryl moiety of diaryl-2-pyrrolidinemethanols was f
Recyclable Polyurea-Microencapsulated Pd(0) Nanoparticles: An Efficient Catalyst for Hydrogenolysis of Epoxides
Ley, Steven V.,Mitchell, Claire,Pears, David,Ramarao, Chandrashekar,Yu, Jin-Quan,Zhou, Wuzong
, p. 4665 - 4668 (2007/10/03)
(Matrix presented) Pd nanoparticles (～2 nm in size) microencapsulated in polyurea is an efficient and recyclable catalyst for reductive ring-opening hydrogenolysis of epoxides, using either HCOOH/Et3N or H2 as a hydrogen donor.
