10294-00-5Relevant academic research and scientific papers
Organocatalytic epoxidation and allylic oxidation of alkenes by molecular oxygen
Orfanidou, Maria,Petsi, Marina,Zografos, Alexandros L.
supporting information, p. 9172 - 9178 (2021/11/30)
Pyrrole-proline diketopiperazine (DKP) acts as an efficient mediator for the reduction of dioxygen by Hantzsch ester under mild conditions to allow the aerobic metal-free epoxidation of electron-rich alkenes. Mechanistic crossovers are underlined, explaining the dual role of Hantzsch ester as a reductant/promoter of the DKP catalyst and a simultaneous competitor for the epoxidation of alkenes when HFIP is used as a solvent. Expansion of this protocol to the synthesis of allylic alcohols was achieved by adding a catalytic amount of selenium dioxide as an additive, revealing a superior method to the classical application of t-BuOOH as a selenium dioxide oxidant.
Epoxidation of strained alkenes catalysed by (1,2-dimethyl-4(1H)pyridinone-3-olate)2MnIIICl
Robinson-Miller, Adam P.,Wyatt, Mark F.,Tétard, David
, p. 376 - 390 (2015/01/30)
The mild epoxidation of strained alkenes using (DMPO)2MnCl catalyst (DMPO = 1,2-dimethyl-4(1H)-pyridinone-3-olate) in the presence of various oxidants was studied. Hydrogen peroxide and monopersulfate were found to be the best oxidants when used with imidazole in acetonitrile at 4 °C, with up to 94% conversion. Dismutation of hydrogen peroxide was also observed when used as an oxidant. The epoxidation using hydrogen peroxide or monoperoxysulfate appears to be mild and very selective for strained alkenes. A mechanism is proposed where imidazole is required for activation of the oxidant and where a detected MnV = O species is proposed as the active species. Competitive reaction between H2O2 and the substrate for the active species is proposed and homolytic vs heterolytic scissions of the OO bond of the oxidant are discussed.
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.
Diverse pathways for the palladium(II)-mediated oxidation of olefins by tert-butylhydroperoxide
Yu, Jin-Quan,Corey
, p. 2727 - 2730 (2007/10/03)
(Matrix presented) New procedures are described for the palladium-catalyzed oxidation of olefins by tert-butylhydroperoxide under slightly basic conditions in CH2Cl2 solution at 0-25°C.
AUTOOXIDATION OF ARYLCYCLOALKENES: A METHOD FOR THE PREPARATION OF EPOXIDES
Sethi, Shanti C.,Natu, Arun D.,Wadia, Murzban S.
, p. 221 - 228 (2007/10/02)
A method for the preparation of arylcycloalkene epoxides has been developed via the autooxidation of the corresponding arylcycloalkenes.
