Highly Active Palladium Catalyst for the Sonogashira Coupling Reaction of Unreactive Aryl Chlorides
作者:Dong-Hwan Lee、Young-Jun Kwon、Myung-Jong Jin
DOI:10.1002/adsc.201100747
日期:2011.11
communication reports on the β-diketiminatophosphane palladium-catalyzed copper-free Sonogashira coupling of arylchlorides with alkynes. A catalyst loading of 0.5 mol% is sufficient to achieve high performance under relatively mild reaction conditions. Furthermore, dialkynylbenzenes are efficiently prepared by one-pot double Sonogashira couplings of aryl dichlorides.
Volume parameters of some Diels-Alder reactions involving C=C, C=S, and N=N bonds
作者:V. D. Kiselev、E. A. Kashaeva、L. N. Potapova、G. G. Iskhakova、A. I. Konovalov
DOI:10.1007/s11172-006-0075-8
日期:2005.9
up to 1000 kg cm−2 on the rate constants of the Diels-Alderreactions of maleic anhydride with 1,2,3,4-tetraphenylcyclopentadiene and with 6,13-dichloropentacene, of 4-phenyl-1,2,4-triazoline-3,5-dione with hexachlorocyclopentadiene, and of thiobenzophenone with isoprene was studied at 25 °C. The volume parameters and ratios of the activation to reaction volumes make it possible to exclude electrostriction
高达 1000 kg cm-2 的静水压力对马来酸酐与 1,2,3,4-四苯基环戊二烯和 4-苯基-的 6,13-二氯并五苯的 Diels-Alder 反应速率常数的影响在 25 °C 下研究了 1,2,4-三唑啉-3,5-二酮与六氯环戊二烯以及噻二苯甲酮与异戊二烯。体积参数和活化与反应体积的比率使得在所有研究的反应中的过渡态溶剂化过程中排除溶剂的电致伸缩成为可能,这对应于过渡态的非极性性质。
Synthesis and Characterization of 6,13-Diamino-Substituted Pentacenes
A series of 6,13‐diamino‐substituted pentacenes 1 a–d has been prepared and characterized as a new class of pentacene derivatives with strong donor ability and enhanced solubility in common organic solvents. The spectroelectrochemical and DFT studies revealed that the two‐electron oxidation process was accompanied by the substantial structural change into a butterfly‐like conformation of the pentacene
A facile method was developed to synthesize pentacene derivative 6,13-dichloropentacene (DCP) in high yield. The absorption spectra and electrochemistry results showed that the introduction of chlorine substituents lowered the HOMO energy level and increased the environmental stability of the compound. Single crystal diffraction revealed that DCP adopted slipped face-to-face packing mode. π–π and C–H⋯Cl interactions were observed in the crystals. The thin film transistor characteristics showed that DCP exhibited high mobility (0.20 cm2 V−1 s−1), low threshold voltage (∼−2.0 V) and good stability.