1821-12-1Relevant articles and documents
Schwenk,Papa,Ginsberg
, p. 576 (1943)
A Core–Shell-Structured Silver Nanowire/Nitrogen-Doped Carbon Catalyst for Enhanced and Multifunctional Electrofixation of CO2
Yang, Heng-Pan,Zhang, Han-Wen,Wu, Yu,Fan, Liang-Dong,Chai, Xiao-Yan,Zhang, Qian-Ling,Liu, Jian-Hong,He, Chuan-Xin
, p. 3905 - 3910 (2018)
Numerous catalysts have been successfully introduced for CO2 fixation in aqueous or organic systems. However, a single catalyst showing activity in both solvent types is still rare, to the best of our knowledge. We developed a core–shell-structured AgNW/NC700 composite using a Ag nanowire (NW) core encapsulated by a N-doped carbon (NC) shell at 700 °C. Through control experiments and density functional theory calculations, it was confirmed that Ag nanowires acted as the active sites for CO2 fixation and the uniformly coating of N-doped carbon created a CO2-rich environment around the Ag nanowires, which could significantly improve the catalytic activity of Ag nanowires for electrochemical CO2 fixation. Under mild conditions, up to 96 % faradaic efficiency of CO, 95 % yield of Ibuprofen and 92 % yield of propylene carbonate could be obtained in the electrochemical CO2 direct reduction, carboxylation and cycloaddition, respectively, using the same AgNWs/NC700 catalyst. These results might provide an alternative strategy for efficient electrochemical fixation of CO2.
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Adametz et al.
, p. 1453 (1962)
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The marked difference in conformational behavior of the two diastereomers of 7-substituted-1,1-dichloro-7b-((Z)-8-chloro-6,7-dihydro-5H-benzo[7]annulen-9- yl)-1a,2,3,7b-tetrahydro-1H-cyclopropa[a]naphthalene, single crystal X-ray, 1H NMR and AM1 studies
Roshan, Hamid,Rashidi-Ranjbar, Parviz
, p. 59 - 65 (2010)
The 7-substituted of 1 and 2 were synthesized and conformational analysis carried out. While 7-substituted of 2 show two conformers in solution, 7-substituted of 1 show only one form in solution. AM1 semi-empirical molecular orbital calculations show that the conformation of cycloheptadiene ring in 1 and 2 is a twist boat form. In this conformation, the C-7 substituents can be oriented in pseudo equatorial (exo) and pseudo axial (endo) positions. The 3J calculation with Haasnoot equation on optimized structure of 2 reproduces the observed 3J coupling constants in exo and endo forms. Ring inversion of cycloheptadiene moiety in substituted 2 interconvert the e′-a′ (exo-endo) positions. The 3J calculation on optimized structure of 1 shows that 7-substitution is in pseudo equatorial (exo) direction, as found in the crystal structure of 1a by single crystal X-ray crystallography. The barrier to ring inversion in 2a is determined by dynamic 1H NMR spectroscopy to be ΔG≠(335K) = 68.0 ± 0.5 kJ/mol.
Pd-Catalyzed Regioselective Branched Hydrocarboxylation of Terminal Olefins with Formic Acid
Chu, Jianxiao,Guo, Jianqiong,Ren, Wenlong,Shi, Yian,Shi, Yuan,Wang, Mingzhou,Zhou, Jintao
supporting information, p. 886 - 891 (2022/02/07)
A regioselective Pd-catalyzed hydrocarboxylation of terminal olefins with HCOOH is described. A wide variety of branched carboxylic acids can readily be obtained with high regioselectivities under mild reaction conditions. The reaction is operationally simple and requires no handling of toxic CO. The ligand and LiCl are important factors for reaction reactivity and selectivity.
Palladium-Catalyzed Direct C-H Arylation of 3-Butenoic Acid Derivatives
Yang, Shan,Liu, Lingling,Zhou, Zheng,Huang, Zhibin,Zhao, Yingsheng
supporting information, p. 296 - 299 (2021/01/13)
We report herein a direct method to synthesize 4-aryl-3-butenoic acid through a carboxylic-acid-directed oxidative Heck reaction. The various 4-aryl-3-butenoic acids are easily prepared in moderate to good yields. In view of the promising bioactivity of 4-phenyl-3-butenoic acid previously reported, its derivatives reported here may be bioactive.
