- Iron-catalyzed epoxidation of aromatic olefins and 1,3-dienes
-
The combination of iron(III) chloride, pyridine-2,6-dicarboxylic acid and formamidine ligands allows for the epoxidation of styrenes and conjugated dienes in excellent chemoselectivity and yields.
- Schroeder, Kristin,Enthaler, Stephan,Join, Benoit,Junge, Kathrin,Beller, Matthias
-
-
Read Online
- Aerobic oxidation of the C-H bond under ambient conditions using highly dispersed Co over highly porous N-doped carbon
-
Highly dispersed Co sites in highly porous N-doped carbon (Co-NC) were synthesized by high-temperature pyrolysis of Zn/Co bimetallic zeolitic imidazolate framework-8 (CoxZn100-x-ZIF). Wide characterization indicated that the pyrolysis atmosphere and temperature play crucial roles in the metal dispersion and pore structure of the resulting materials. A hydrogen treatment at elevated temperatures is found to favour the Zn volatilization and restrict the pore shrinkage of the ZIF precursor, thus yielding efficient catalysts with highly dispersed Co, a high surface area (1090 m2 g-1) and pore volume (0.89 cm3 g-1). When used as a catalyst for aerobic oxidation of ethylbenzene (EB), Co1Zn99-ZIF-800-H2 contributes to 98.9% EB conversion and 93.1% ketone selectivity under mild conditions (60 °C, 1 atm O2), which is 41.3 times more active in comparison to the ZIF-67-derived Co catalyst. Co-NC is stable and could be reused four times without obvious deactivation. This catalyst displays good chemoselectivity to the corresponding ketones when using a broad scope of hydrocarbon compounds.
- Nie, Renfeng,Chen, Jingwen,Chen, Minda,Qi, Zhiyuan,Goh, Tian-Wei,Ma, Tao,Zhou, Lin,Pei, Yuchen,Huang, Wenyu
-
p. 1461 - 1466
(2019/03/26)
-
- LIQUID PHASE OXIDATION OF CYCLIC POLYOLEFINS WITH MOLECULAR OXYGEN. PART II. CIS,CIS-1,5-CYCLOOCTADIENE AUTOOXIDATION
-
The autooxidation of 1,5-cyclooctadiene has been studied.Cyclooctadiene easily undergoes oxidation by molecular oxygen.Depending on the reaction procedure and the degree of conversion, polymeric or monomeric oxidated products are the dominating products with the preservation of eight-membered ring.The content of 1,2-epoxycyclooctene-5 in the product may exceed 50percent.The reaction was found to be of a free-radical character.An initiation and propagation scheme of the autooxidation is proposed.
- Giezynski, Roman,Pala, Magdalena
-
-
- Studies on the Autoxidation of Some Monocyclic Olefins
-
The autoxidations of cyclopentene, cyclohexene, cycloheptene, cyclooctene, cycloocta-1,5-diene, 1-methylcyclopentene, 1-methylcyclohexene, 1-methylcycloheptene, 1-methylcyclooctene, methylene cyclopentene, and methylene cyclohexene with pure oxygen under normal pressure were studied.The epoxides formed were determined gaschromatographically.In most cases also the products of allylic oxidation were analyzed and their structures elucidated after reduction to the corresponding allyl alcohols.The portions of high boiling or polymeric products which could not be detected gaschromatographically and also the real yields of epoxides were determined by balance experiments in the presence of inert internal standards.
- Blau, K.,Mueller, U.,Pritzkow, W.,Schmidt-Renner, W.,Sedshaw, Z.
-
p. 915 - 932
(2007/10/02)
-