5 research outputs found
Ruthenium Catalyzed Hydrogenation of Aldehyde with Synthesis Gas
The hydrogenation of aldehyde utilizing
synthesis gas as a dihydrogen
source was examined with various ruthenium catalysts, among which
Ru–cyclopentadienone complexes (Shvo-type catalysts) exhibited
higher activity than others. DFT calculations proved that the exchange
of coordinated carbon monoxide by dihydrogen is relatively preferable
in Shvo-type catalysts compared to others, which is a pre-equilibrium
for the generation of the hydrogenation-active species
Tandem Hydroformylation/Hydrogenation of Alkenes to Normal Alcohols Using Rh/Ru Dual Catalyst or Ru Single Component Catalyst
The catalyst system for tandem hydroformylation/hydrogenation
of
terminal alkenes to the corresponding homologated normal alcohol was
developed. The reaction mechanism for the Rh/Ru dual catalyst was
investigated by real-time IR monitoring experiments and <sup>31</sup>P NMR spectroscopy, which proved the mutual orthogonality of Rh-catalyzed
hydroformylation and Ru-catalyzed hydrogenation. Detailed investigation
about Ru-catalyzed hydrogenation of undecanal under H<sub>2</sub>/CO
pressure clarified different kinetics from the hydrogenation under
H<sub>2</sub> and gave a clue to design more active hydrogenation
catalysts under H<sub>2</sub>/CO atmosphere. The solely Ru-catalyzed
normal selective hydroformylation/hydrogenation is also reported
Tandem Hydroformylation/Hydrogenation of Alkenes to Normal Alcohols Using Rh/Ru Dual Catalyst or Ru Single Component Catalyst
The catalyst system for tandem hydroformylation/hydrogenation
of
terminal alkenes to the corresponding homologated normal alcohol was
developed. The reaction mechanism for the Rh/Ru dual catalyst was
investigated by real-time IR monitoring experiments and <sup>31</sup>P NMR spectroscopy, which proved the mutual orthogonality of Rh-catalyzed
hydroformylation and Ru-catalyzed hydrogenation. Detailed investigation
about Ru-catalyzed hydrogenation of undecanal under H<sub>2</sub>/CO
pressure clarified different kinetics from the hydrogenation under
H<sub>2</sub> and gave a clue to design more active hydrogenation
catalysts under H<sub>2</sub>/CO atmosphere. The solely Ru-catalyzed
normal selective hydroformylation/hydrogenation is also reported
Tandem Hydroformylation/Hydrogenation of Alkenes to Normal Alcohols Using Rh/Ru Dual Catalyst or Ru Single Component Catalyst
The catalyst system for tandem hydroformylation/hydrogenation
of
terminal alkenes to the corresponding homologated normal alcohol was
developed. The reaction mechanism for the Rh/Ru dual catalyst was
investigated by real-time IR monitoring experiments and <sup>31</sup>P NMR spectroscopy, which proved the mutual orthogonality of Rh-catalyzed
hydroformylation and Ru-catalyzed hydrogenation. Detailed investigation
about Ru-catalyzed hydrogenation of undecanal under H<sub>2</sub>/CO
pressure clarified different kinetics from the hydrogenation under
H<sub>2</sub> and gave a clue to design more active hydrogenation
catalysts under H<sub>2</sub>/CO atmosphere. The solely Ru-catalyzed
normal selective hydroformylation/hydrogenation is also reported
Photoprecursor Approach Enables Preparation of Well-Performing Bulk-Heterojunction Layers Comprising a Highly Aggregating Molecular Semiconductor
Active-layer
morphology critically affects the performance of organic photovoltaic
cells, and thus its optimization is a key toward the achievement of
high-efficiency devices. However, the optimization of active-layer
morphology is sometimes challenging because of the intrinsic properties
of materials such as strong self-aggregating nature or low miscibility.
This study postulates that the “photoprecursor approach”
can serve as an effective means to prepare well-performing bulk-heterojunction
(BHJ) layers containing highly aggregating molecular semiconductors.
In the photoprecursor approach, a photoreactive precursor compound
is solution-deposited and then converted in situ to a semiconducting
material. This study employs 2,6-di(2-thienyl)anthracene (DTA) and
[6,6]-phenyl-C<sub>71</sub>-butyric acid methyl ester as p- and n-type
materials, respectively, in which DTA is generated by the photoprecursor
approach from the corresponding α-diketone-type derivative DTADK.
When only chloroform is used as a cast solvent, the photovoltaic performance
of the resulting BHJ films is severely limited because of unfavorable
film morphology. The addition of a high-boiling-point cosolvent, <i>o</i>-dichlorobenzene (<i>o</i>-DCB), to the cast
solution leads to significant improvement such that the resulting
active layers afford up to approximately 5 times higher power conversion
efficiencies. The film structure is investigated by two-dimensional
grazing-incident wide-angle X-ray diffraction, atomic force microscopy,
and fluorescence microspectroscopy to demonstrate that the use of <i>o</i>-DCB leads to improvement in film crystallinity and increase
in charge-carrier generation efficiency. The change in film structure
is assumed to originate from dynamic molecular motion enabled by the
existence of solvent during the in situ photoreaction. The unique
features of the photoprecursor approach will be beneficial in extending
the material and processing scopes for the development of organic
thin-film devices