33512-02-6Relevant academic research and scientific papers
Chiral C2-Symmetric Aminomethylbinaphthol as Synergistic Catalyst for Asymmetric Epoxidation of Alkylidenemalononitriles: Easy Access to Chiral Spirooxindoles
Ogino, Eri,Nakamura, Ayu,Kuwano, Satoru,Arai, Takayoshi
supporting information, p. 1980 - 1985 (2021/03/03)
Chiral C2-symmetric 3,3′-bis((R,R)-2-naphthylethylaminomethyl)-(R)-binaphthol (AMB4) functions as an efficient organocatalyst for the asymmetric epoxidation of various alkylidenemalononitriles. The spiro-epoxyoxindole products obtained from isatilidenemal
Pyrenediones as versatile photocatalysts for oxygenation reactions with: In situ generation of hydrogen peroxide under visible light
Zhang, Yuannian,Yang, Xin,Tang, Haidi,Liang, Dong,Wu, Jie,Huang, Dejian
supporting information, p. 22 - 27 (2020/01/13)
Pyrenediones (PYDs) are efficient photocatalysts for three oxygenation reactions: Epoxidation of electron deficient olefins, oxidative hydroxylation of organoborons, and oxidation of sulfides via in situ generation of H2O2 under visible light irradiation, using oxygen as a terminal oxidant and IPA as a solvent and a hydrogen donor.
Hypervalent Iodine(III)-Catalyzed Epoxidation of β-Cyanostyrenes
Mangaonkar, Saeesh R.,Singh, Fateh V.
, p. 4473 - 4486 (2019/11/21)
A convenient approach for the synthesis of β-cyanoepoxides is illustrated by iodine(III)-catalyzed epoxidation of electron-deficient β-cyanostyrenes, wherein the active catalytic iodine(III) species was generated in situ. The epoxidation of β-cyanostyrenes was performed using 10 molpercent PhI as precatalyst in the presence of 2.0 equivalents Oxone as an oxidant and 2.4 equivalents of TFA as an additive at room temperature under ultrasonic radiations. The β-cyanoepoxides were isolated in good to excellent yields in a short reaction time.
Access to thiomorpholin-3-one derivatives: [3 + 3]-cycloadditions of α-chlorohydroxamates and 1,4-dithiane-2,5-diol
He, Zhao-Lin,Chen, Yi,Wang, Xiaohua,Ni, Mingwang,Wang, Gang
, (2019/07/22)
A protocol of [3 + 3]-cycloaddition was proposed for the synthesis of 2H-1,4-thiazin-3(4H)-ones and thiomorpholine-3,5-diones from α-chlorohydroxamates and 1,4-dithiane-2,5-diol. This direct and practical method provides a novel and rapid approach for the
Epoxidation of vinyl cyanides by calcium hypochlorite under catalyst- and solvent-free conditions
Mirhashemi,Amrollahi
, p. 2661 - 2663 (2018/06/06)
In this paper, epoxidation of a wide range of alkenes by calcium hypochlorite (Ca(OCl)2) was investigated under catalyst- and solvent-free conditions. It was noticed that the highest yield was achieved with crushing, when the reaction was betwe
Ultrasound-assisted rapid synthesis of β-cyanoepoxides using hypervalent iodine reagents
Singh, Fateh V.,Mangaonkar, Saeesh R.,Kole, Priyanka B.
supporting information, p. 2169 - 2176 (2018/07/21)
An elegant approach for the rapid synthesis of β-cyanoepoxides 3 by the epoxidation of β-cyanostyrenes 1 with PIDA 2a is described. The epoxidation of β-cyanostyrenes 1 was performed with 1.2 equiv. of PIDA 2a in MeCN-H2O (1:1) at room temperature in ultrasonic bath. The epoxidation reactions were completed in short reaction time and β-cyanoepoxides 3 were isolated in 69–94% yields.
Nucleophilic Reactivities of Bleach Reagents
Mayer, Robert J.,Ofial, Armin R.
, p. 2816 - 2820 (2018/05/29)
The nucleophilicities of the oxidants hydroperoxide, hypochlorite, hypobromite, bromite, and peroxymonosulfate were determined by following the kinetics of their reactions with a series of benzhydrylium ions of known electrophilicity (E) in alkaline, aque
Intramolecular Hydrogen-Bonding Modulates the Nucleophilic Reactivity of Ammonium-Peroxycarboxylates
Mayer, Robert J.,Ofial, Armin R.
supporting information, p. 6010 - 6017 (2018/11/10)
The ammonium-peroxycarboxylic acid mesylates derived from γ-aminobutyric acid, β-alanine, and β-piperidinopropionic acid were synthesized and characterized by spectroscopic methods and X-ray crystallography. To study the nucleophilic reactivities of the corresponding ammonium- and amino-peroxycarboxylates, the kinetics of their reactions with a series of benzhydrylium ions (Ar2CH+) were investigated in alkaline, aqueous solutions at 20 °C. Using sequential-mixing stopped-flow UV/Vis photometry, the rates of the reactions of the short-lived nucleophiles with Ar2CH+ were determined and analyzed by the linear free energy relationship lg k = sN(N + E) furnishing nucleophilicity parameters (N, sN) of the peroxycarboxylates. Quantum chemical calculations indicate that the reactivity of the zwitterionic ammonium-peroxycarboxylates is attenuated by intramolecular N–H···O hydrogen bonding.
Solvation Accounts for the Counterintuitive Nucleophilicity Ordering of Peroxide Anions
Mayer, Robert J.,Tokuyasu, Takahiro,Mayer, Peter,Gomar, Jér?me,Sabelle, Stéphane,Mennucci, Benedetta,Mayr, Herbert,Ofial, Armin R.
supporting information, p. 13279 - 13282 (2017/10/17)
The nucleophilic reactivities (N, sN) of peroxide anions (generated from aromatic and aliphatic peroxy acids or alkyl hydroperoxides) were investigated by following the kinetics of their reactions with a series of benzhydrylium ions (Ar2CH+) in alkaline aqueous solutions at 20 °C. The second-order rate constants revealed that deprotonated peroxy acids (RCO3?), although they are the considerably weaker Br?nsted bases, react much faster than anions of aliphatic hydroperoxides (ROO?). Substitution of the rate constants of their reactions with benzhydrylium ions into the linear free energy relationship lg k=sN(N+E) furnished nucleophilicity parameters (N, sN) of peroxide anions, which were successfully applied to predict the rates of Weitz–Scheffer epoxidations. DFT calculations with inclusion of solvent effects by means of the Integral Equation Formalism version of the Polarizable Continuum Model were performed to rationalize the observed reactivities.
Chemoenzymatic Synthesis of α-Cyano Epoxides by a Tandem-Knoevenagel-Epoxidation Reaction
Yang, Fengjuan,Zhang, Xiaowen,Li, Fengxi,Wang, Zhi,Wang, Lei
supporting information, p. 1251 - 1254 (2016/03/16)
An efficient lipase-mediated synthesis of α-cyano epoxides through a tandem-Knoevenagel-epoxidation reaction was explored for the first time. This method provides a green, mild, and convenient route for the synthesis of α-cyano epoxides; moreover, the app
