Studies on selective preparation of aromatic compounds. 15. The Lewis acid catalyzed transalkylation of some tert-butyldiphenylmethanes and -ethanes in aromatic solvents
Catalytic Double C-Cl Bond Activation in CH2Cl2 by Iron(III) Salts with Grignard Reagents
作者:Christopher Kozak、Xin Qian
DOI:10.1055/s-0030-1259922
日期:2011.4
Cross-coupling of Grignard reagents with dichloromethane is achieved using iron(III) catalysts. Aryl- and benzylmagnesium bromides show a range of activity toward double C-Cl bond activation resulting in the insertion of methylene fragments between two equivalents of the nucleophilic partner.
Effective Activation of Strong C−Cl Bonds for Highly Selective Photosynthesis of Bibenzyl via Homo‐Coupling
作者:Qingning Yang、Xiyi Li、Lu Chen、Xiaoyu Han、Feng Ryan Wang、Junwang Tang
DOI:10.1002/anie.202307907
日期:2023.10.23
nanoparticles exhibit robust performance in photocatalytic C−C coupling of inert benzylchloride. Compared to previously reported Cu/TiO2, the selectivity towards bibenzyl increases from 57 to 93 %. Cu loading enhances the reactant adsorption, C−Cl bond activation and charge separation/transfer. The moderate oxidation of 2-propanol by ZnO is a key factor in alleviating the generation of byproduct toluene
负载 Cu 的 ZnO 纳米粒子在惰性氯化苄的光催化 C−C 偶联中表现出强大的性能。与之前报道的Cu/TiO 2相比,联苄的选择性从57%增加到93%。 Cu 负载增强了反应物吸附、C−Cl 键活化和电荷分离/转移。 ZnO对2-丙醇的适度氧化是减轻副产物甲苯生成的关键因素。
What Molecules Are Likely or Unlikely To Undergo Pedal Motions in Crystals?
作者:Jun Harada、Keiichiro Ogawa
DOI:10.1021/cg500962y
日期:2014.10.1
The crystal structures of several (E)-stilbenes and 1,2-diarylethane that have methyl or chloro substituents were examined by variable-temperature X-ray diffraction analysis. All the compounds showed disorders in their crystal structures at least at room temperature. In the crystal structures of the molecules with ortho-methyl groups, the disorder observed at room temperature disappeared at 90 K. The dynamic disorders in these crystals were explained in terms of the conformational changes induced by pedal motions, which were not obstructed by the ortho-methyl groups. In the crystals of the stilbenes with alpha-substituents, however, the populations of the two disordered conformers did not change with temperature, which indicates that the disorders were static and these molecules did not undergo the pedal motions in their crystals. Theoretical calculations on the energy barriers for the pedal motions indicated that the observed restriction of the pedal motion in crystals was originated not only in the intramolecular steric repulsions involving the alpha-substituents but mainly in the steric repulsions between the alpha-substituents and the surrounding molecules in the crystals. The pedal motion can proceed only when the shapes of the molecules do not largely change during the process.
Carbanions. 23. Cleavages of 1,2-diphenylethane and derivatives by cesium-potassium-sodium alloy. Competitive rates of bond scission
作者:Erling Grovenstein、Amjad M. Bhatti、Dean E. Quest、Dibyendu Sengupta、Don VanDerveer
DOI:10.1021/ja00358a018
日期:1983.9
Sengupta, Dibyendu; Grovenstein, E., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1986, vol. 25, p. 185 - 186