Aldehyde/olefin cooxidations: Parallel epoxidation pathways and concerted decomposition of the peroxyacyl-olefin adduct
作者:Kevin R. Lassila、Francis J. Waller、Steven E. Werkheiser、Amy L. Wressell
DOI:10.1016/0040-4039(94)88247-9
日期:1994.10
Aldehyde-mediated olefinepoxidations appear to proceed by parallel peracid and radical addition pathways. For that portion of the reaction proceeding by radical addition, several lines of evidence favor an explanation in which the peroxyacyl-olefinadductdecomposes in a concerted manner to form alkyl radical, CO2, and epoxide.
A novel hexanuclear heteropolyperoxo oxidation catalyst: preparation, X-ray crystal structure and reactions of [NMe<sub>4</sub>]<sub>3</sub>[(MePO<sub>3</sub>){MePO<sub>2</sub>(OH)}W<sub>6</sub>O<sub>13</sub>(O<sub>2</sub>)<sub>4</sub>(OH)<sub>2</sub>(OH<sub>2</sub>)]·4H<sub>2</sub>O
作者:William P. Griffith、Bernardeta C. Parkin、Andrew J. P. White、David J. Williams
DOI:10.1039/c39950002183
日期:——
The crystal structure of the title compound, 1, reveals the presence of two distinct types of tungsten atom in which the four bearing peroxo groups have distorted pentagonal-bipyramidal geometries and the remaining two are octahedral; 1 is an effective catalyst for monoalkene epoxidation, and the oxidation of primary and secondary alcohols, with H2O2 as co-oxidant.
Olefins were smoothly epoxidized under O2 (1 atm) in the presence of a hydrocarbon such as ethylbenzene or tetralin, using N-hydroxyphthalimide (NHPI) and Mo(CO)6 as catalyst; the present reaction involves autoxidation of the hydrocarbon assisted by NHPI and epoxidation of alkenes with the resulting hydroperoxide catalyzed by Mo(CO)6; cis-alkene was epoxidized in a stereospecific manner to form the
Covalent Heterogenization of a Discrete Mn(II) Bis-Phen Complex by a Metal-Template/Metal-Exchange Method: An Epoxidation Catalyst with Enhanced Reactivity
作者:Tracy J. Terry、T. Daniel P. Stack
DOI:10.1021/ja0742030
日期:2008.4.1
along with the epoxidationreactivity once reloaded with manganese. Comparisons of this imprinted material with material synthesized by random grafting of the ligand show that the template method creates more reproducible, solution-like bis-1,10-phenanthroline coordination at a variety of ligand loadings. Olefin epoxidation with peracetic acid shows the imprinted manganese catalysts have improved product
Manganese(II)/Picolinic Acid Catalyst System for Epoxidation of Olefins
作者:Ross A. Moretti、J. Du Bois、T. Daniel P. Stack
DOI:10.1021/acs.orglett.6b00518
日期:2016.6.3
An in situ generated catalyst system based on Mn(CF3SO3)2, picolinic acid, and peracetic acid converts an extensive scope of olefins to their epoxides at 0 °C in <5 min, with remarkable oxidant efficiency and no evidence of radical behavior. Competition experiments indicate an electrophilic active oxidant, proposed to be a high-valent Mn = O species. Ligand exploration suggests a general ligand sphere
基于Mn(CF 3 SO 3)2,吡啶甲酸和过氧乙酸的原位生成的催化剂体系在0°C下于<5分钟内将大量烯烃转化为环氧化物,具有显着的氧化效率并且没有自由基的迹象行为。竞争实验表明,一种亲电子活性氧化剂被认为是高价Mn = O物种。配体探索表明,一般的配体球基序有助于有效氧化。该方法以其简单性和使用廉价试剂来快速获得高附加值产品而得到强调。