71-47-6Relevant articles and documents
Flowing afterglow study of the gas phase nucleophilic reactions of some formyl, acetyl and cyclic esters
Frink, Brian T.,Hadad, Christopher M.
, p. 2397 - 2407 (1999)
A variety of nucleophiles have been investigated for their reactions with formyl and acetyl esters in the gas phase in our flowing afterglow. The reactions that are permitted in the gas phase are more varied than those seen in the condensed phase. The rates of reactions of methyl and ethyl esters as well as various lactones have been undertaken with various nucleophiles: H2N-, HO-, CH3O, NCCH2-, F-, CH3C(=O)CH2-, CH3S- and O2NCH2-. For example, the reaction rate of NCCH2- + HCO2CH2CH3 has been found to be (1.3 ± 0.2) x 10-10 cm3 molecule-1 s-1 and the only product is HC(O-)=CHCN which results from nucleophilic acyl substitution (BAC2) followed by a proton transfer within the ion-molecule complex. Other reaction mechanisms that have been observed include β-elimination (E2), bimolecular nucleophilic substitution at the alkyl group (BAL2), and the Riveros reaction (elimination of CO). A mechanism for the F- + HCO2CH3 reaction has been determined at the B3LYP/6-31 + G(d) level. Most notably, channels were determined computationally (6AL2 and Riveros), and these channels are also observed experimentally. Furthermore, the BAC2 pathway which proceeds via nucleophilic attack on the carbonyl group also leads to the Riveros products, F-(CH3OH) and CO.
Symmetry-Broken Au–Cu Heterostructures and their Tandem Catalysis Process in Electrochemical CO2 Reduction
Jia, Henglei,Yang, Yuanyuan,Chow, Tsz Him,Zhang, Han,Liu, Xiyue,Wang, Jianfang,Zhang, Chun-yang
, (2021/04/27)
Symmetry-breaking synthesis of colloidal nanocrystals with desired structures and properties has aroused widespread interest in various fields, but the lack of robust synthetic protocols and the complex growth kinetics limit their practical applications. Herein, a general strategy is developed to synthesize the Au–Cu Janus nanocrystals (JNCs) through the site-selective growth of Cu nanodomains on Au nanocrystals, which is directed by the substantial lattice mismatch between them, with the assistance of judicious manipulation of the growth kinetics. This strategy can work on Au nanocrystals with different architectures for the achievement of diverse asymmetric Au–Cu hybrid nanostructures. Of particular note, the obtained Au nanobipyramids (Au NBPs)-based JNCs facilitate the conversion of CO2 to C2 hydrocarbon production during electrocatalysis, with the Faradaic efficiency and maximum partial current density being 4.1-fold and 6.4-fold higher than those of their monometallic Cu counterparts, respectively. The excellent electrocatalytic performances benefit from the special design of the Au–Cu Janus architectures and their tandem catalysis mechanism as well as the high-index facets on Au nanocrystals. This research provides a new approach to synthesize various hybrid Janus nanostructures, facilitating the study of structure-function relationship in the catalytic process and the rational design of efficient heterogeneous electrocatalysts.
Hydrogen and chemicals from alcohols through electrochemical reforming by Pd-CeO2/C electrocatalyst
Bellini, Marco,Pagliaro, Maria V.,Marchionni, Andrea,Filippi, Jonathan,Miller, Hamish A.,Bevilacqua, Manuela,Lavacchi, Alessandro,Oberhauser, Werner,Mahmoudian, Jafar,Innocenti, Massimo,Fornasiero, Paolo,Vizza, Francesco
, (2021/01/25)
The development of low-cost and sustainable hydrogen production is of primary importance for a future transition to sustainable energy. In this work, the selective and simultaneous production of pure hydrogen and chemicals from renewable alcohols is achieved using an anion exchange membrane electrolysis cell (electrochemical reforming) employing a nanostructured Pd-CeO2/C anode. The catalyst exhibits high activity for alcohol electrooxidation (e.g. 474 mA cm?2 with EtOH at 60 °C) and the electrolysis cell produces high volumes of hydrogen (1.73 l min?1 m?2) at low electrical energy input (Ecost = 6 kWh kgH2?1 with formate as substrate). A complete analysis of the alcohol oxidation products from several alcohols (methanol, ethanol, 1,2-propandiol, ethylene glycol, glycerol and 1,4-butanediol) shows high selectivity in the formation of valuable chemicals such as acetate from ethanol (100%) and lactate from 1,2-propandiol (84%). Importantly for industrial application, in batch experiments the Pd-CeO2/C catalyst achieves conversion efficiencies above 80% for both formate and methanol, and 95% for ethanol.
