27200-79-9Relevant articles and documents
Gold nanoparticles supported on magnesium oxide nanorods for oxidation of alcohols
Emayavaramban,Ganesh Babu,Karvembu,Kadirvelu,Dharmaraj
, p. 2517 - 2526 (2016)
Gold nanoparticles supported on magnesium oxide nanorods (Au-MgO) have been synthesised by a solution based chemical reduction method. Au-MgO nanorods were found to be an efficient heterogeneous catalyst for oxidation of alcohols with hydrogen peroxide in aqueous medium at room temperature. To find out the best reaction conditions for oxidation, optimization of catalyst quantity, solvent, mole equivalence of hydrogen peroxide were carried out. The scope of the reaction was extended to several aromatic and aliphatic alcohols, product yields were quantified by gas chromatography (GC) and GC/mass spectroscopy. Heterogeneity and reusability tests were performed. The use of water as a solvent and hydrogen peroxide as co-catalyst at room temperature makes the reaction interesting from sustainable development point of view.
Aerobic epoxidation of styrene over Zr-based metal-organic framework encapsulated transition metal substituted phosphomolybdic acid
Hu, Dianwen,Song, Xiaojing,Zhang, Hao,Chang, Xinyu,Zhao, Chen,Jia, Mingjun
, (2021/04/19)
Catalytic epoxidation of styrene with molecular oxygen is regarded as an eco-friendly alternative to producing industrially important chemical of styrene oxide (STO). Recent efforts have been focused on developing highly active and stable heterogeneous catalysts with high STO selectivity for the aerobic epoxidation of styrene. Herein, a series of transition metal monosubstituted heteropolyacid compounds (TM-HPAs), such as Fe, Co, Ni or Cu-monosubstituted HPA, were encapsulated in UiO-66 frameworks (denoted as TM-HPA@UiO-66) by direct solvothermal method, and their catalytic properties were investigated for the aerobic epoxidation of styrene with aldehydes as co-reductants. Among them, Co-HPA@UiO-66 showed relatively high catalytic activity, stability and epoxidation selectivity at very mild conditions (313 K, ambient pressure), that can achieve 82 % selectivity to STO under a styrene conversion of 96 % with air as oxidant and pivalaldehyde (PIA) as co-reductant. In addition, the hybrid composite catalyst can also efficiently catalyze the aerobic epoxidation of a variety of styrene derivatives. The monosubstituted Co atoms in Co-HPA@UiO-66 are the main active sites for the aerobic epoxidation of styrene with O2/PIA, which can efficiently converting styrene to the corresponding epoxide through the activation of the in-situ generated acylperoxy radical intermediate.
B(C6F5)3-catalyzed tandem protonation/deuteration and reduction of: In situ -formed enamines
Wu, Rongpei,Gao, Ke
supporting information, p. 4032 - 4036 (2021/05/19)
A highly efficient B(C6F5)3-catalyzed tandem protonation/deuteration and reduction of in situ-formed enamines in the presence of water and pinacolborane was developed. Regioselective β-deuteration of tertiary amines was achieved with high chemo- and regioselectivity. D2O was used as a readily available and cheap source of deuterium. Mechanistic studies indicated that B(C6F5)3 could activate water to promote the protonation and reduction of enamines. This journal is