- Photoredox-Catalyzed Simultaneous Olefin Hydrogenation and Alcohol Oxidation over Crystalline Porous Polymeric Carbon Nitride
-
Booming of photocatalytic water splitting technology (PWST) opens a new avenue for the sustainable synthesis of high-value-added hydrogenated and oxidized fine chemicals, in which the design of efficient semiconductors for the in-situ and synergistic utilization of photogenerated redox centers are key roles. Herein, a porous polymeric carbon nitride (PPCN) with a crystalline backbone was constructed for visible light-induced photocatalytic hydrogen generation by photoexcited electrons, followed by in-situ utilization for olefin hydrogenation. Simultaneously, various alcohols were selectively transformed to valuable aldehydes or ketones by photoexcited holes. The porosity of PPCN provided it with a large surface area and a short transfer path for photogenerated carriers from the bulk to the surface, and the crystalline structure facilitated photogenerated charge transfer and separation, thus enhancing the overall photocatalytic performance. High reactivity and selectivity, good functionality tolerance, and broad reaction scope were achieved by this concerted photocatalysis system. The results contribute to the development of highly efficient semiconductor photocatalysts and synergistic redox reaction systems based on PWST for high-value-added fine chemical production.
- Qiu, Chuntian,Sun, Yangyang,Xu, Yangsen,Zhang, Bing,Zhang, Xu,Yu, Lei,Su, Chenliang
-
p. 3344 - 3350
(2021/07/26)
-
- Efficient Water Reduction with sp3-sp3 Diboron(4) Compounds: Application to Hydrogenations, H–D Exchange Reactions, and Carbonyl Reductions
-
A series of crystalline sp3-sp3 diboron(4) compounds were synthesized and shown to promote the facile reduction of water with dihydrogen formation. The application of these diborons as simple and effective dihydrogen and dideuterium sources was demonstrated by conducting a series of selective reductions of alkynes and alkenes, and hydrogen–deuterium exchange reactions using two-chamber reactors. Finally, as the water reduction reaction generates an intermediate borohydride species, a range of aldehydes and ketones were reduced by using water as the hydride source.
- Flinker, Mathias,Yin, Hongfei,Juhl, René W.,Eikeland, Espen Z.,Overgaard, Jacob,Nielsen, Dennis U.,Skrydstrup, Troels
-
supporting information
p. 15910 - 15915
(2017/11/23)
-
- end alkene multi-fluorine diaryl acetylene liquid crystal compound and its preparation method
-
The invention relates to an alkene-terminated polyfluorinated diaryl acetylene liquid crystal compound and a synthesis method thereof. The compound is shown in the structural formula I as shown in the specification, wherein in the structural formula I, (F)m and (F)n both refer to fluorine atom substitutes; m and n refer to the substitute number of fluorine atoms, and the value thereof is 0-2; x refers to the number of connected methylene, and the value thereof is 0-3; and R refers to C1-C15 alkyls, C1-C15 alkenyls, C1-C15 alkoxy and C1-C15 enyloxy. According to the invention, because the compound is synthesized through adopting classic reactions such as nucleophilic substitution, coupling reaction, and the like, the operation is simple, and the yield and purity of products are high; and the compound has the advantages of large negative dielectric anisotropy, low melting point, wide liquid crystal phase interval, large double refraction, and the like, and can be applied to a dual-frequency liquid crystal display mode.
- -
-
Paragraph 0030
(2017/02/23)
-
- A green approach for the decoration of Pd nanoparticles on graphene nanosheets: An in situ process for the reduction of C-C double bonds and a reusable catalyst for the Suzuki cross-coupling reaction
-
A new strategy for in situ synthesis of palladium nanoparticles (Pd NPs) decorated on reduced graphene oxide (rGO) nanosheets with controlled size and shape is reported. This strategy was designed as three processes in one pot, namely, (a) reduction of graphene oxide, (b) formation of Pd NPs on the rGO nanosheets and (c) simultaneous reduction of olefin. In this synthesis process, a hydrogen atmosphere was used to develop the Pd NPs-rGO nanocatalyst, which is reusable and easily separable. The influence of the size and morphology of the Pd-rGO-H2 catalyst on the catalytic activity in the Suzuki cross-coupling reaction was investigated by comparing with other catalysts, Pd-rGO-As and Pd-rGO-Gl, and they were synthesized by different reducing agents, ascorbic acid and glucose, respectively. The catalysts were characterized by electron microscopy (HRTEM, SEM), FT-IR, XRD and XPS. The Pd-rGO-H2 catalyst was found to possess excellent catalytic activity and recyclability in the Suzuki cross-coupling reaction under mild reaction conditions.
- Hussain, Najrul,Borah, Ashwini,Darabdhara, Gitashree,Gogoi, Pranjal,Azhagan, Vedi Kuyil,Shelke, Manjusha V.,Das, Manash R.
-
p. 6631 - 6641
(2015/08/06)
-
- A recyclable Au(I) catalyst for selective homocoupling of arylboronic acids: Significant enhancement of nano-surface binding for stability and catalytic activity
-
Au nanoparticles stabilized by polystyrene-co-polymethacrylic acid microspheres (PS-co-PMAA) were prepared and characterized via X-ray diffraction (XRD), and transmission electron microscope (TEM). The Au nanoparticles supported on the microspheres showed highly selective catalytic activity for homo-coupling reactions of arylboronic acids in a system of aryl-halides and arylboronic acids. X-ray photoelectron spectroscopy (XPS) spectra of the catalyst shows large amounts of Au(l) complexes band to the surface of the Au nanoparticles, which contributes to the selective homocoupling of the arylboronic acids. More importantly, this supported Au complex is a highly recyclable catalyst. The supported Au catalyst can be recycled and reused at least 6 times for a phenylboronic acid reactant, whereas the parent complex shows very low catalytic activity for this compound. The high catalytic activity of this material is attributed to: (1) the high surface to volume ratio which leads to more active sites being exposed to reactants; (2) the strong surface binding of the Au nanoparticle to the Au(1) complexes, which enhances both the stability and the catalytic activity of these complexes. Copyright
- Zhang, Xin,Zhao, Haitao,Wang, Jianhui
-
experimental part
p. 5153 - 5160
(2011/12/15)
-
- Sulfonamides for treatment of endothelin-mediated disorders
-
Thienylsulfonamides and their pharmaceutically acceptable derivatives, pharmaceutical compositions, articles of manufacture, combinations, lyophilized powders and methods for the treatment of endothelin diseases using these formulations and sulfonamides a
- -
-
-
- Sulfonamides for treatment of endothelin-mediated disorders
-
Thienyl-, furyl- and pyrrolyl-sulfonamides, pharmaceutically-acceptable salts of sulfonamides, formulations of salts and the sulfonamides, and methods for modulating or altering the activity of the endothelin family of peptides using the formulations and
- -
-
-
- Biphenylsulfonamides and derivatives thereof that modulate the activity of endothelin
-
Biphenylsulfonamides and methods for modulating or altering the activity of the endothelin family of peptides are provided. In particular, bicyclic or tricyclic carbon or heterocyclic ring biphenylsulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided.
- -
-
-
- Transformation of mutagenic aromatic amines into non-mutagenic species by alkyl substituents: Part II: Alkylation far away from the amino function
-
Alkyl and trifluoromethyl derivatives of 4-aminobiphenyl (1) (4ABP) and 2-aminofluorene (7) (2AF) were synthesised and assayed for mutagenicity using Salmonella typhimurium tester strains TA98 and TA100 with and without the addition of S9 mix. Modification of 1 was achieved by attachment of alkyl groups (methyl, ethyl, iso-propyl, n-butyl, tert-butyl) and a trifluoromethyl group (CF3) in the 4′-position, the 3′-position (Me, CF3) and the 3′-, 5′-positions (DiMe, DiCF3). Compound 7 was modified by introduction of alkyl groups (methyl, tert-butyl, adamantyl) and a trifluoromethyl group (CF3) in the 7-position. The derivatives of 1 and 7 show for groups with growing steric demand decreased mutagenic activity. The bulkiest groups (CF3, tert-butyl and adamantyl) induce the strongest effects on the mutagenicity. It was even possible to eliminate the mutagenicity of 1 and 7 by introduction of such substituents. In the last part of the work, we compared the experimental mutagenicities with calculated values derived from QSAR correlations. Our findings show that the predictions for aromatic amines with bulky substituents were generally too high. The strongest deviations were observed in the case of the CF3-, tert-butyl- and the adamantyl-group. Only the parent compounds and derivatives with small alkyl groups were predicted well. These investigations show that "large" substituents have an influence on the mutagenicity caused by their steric demand. To predict the correct mutagenicities of such compounds, it is necessary to introduce steric parameters in the respective QSAR equations which will be done in a forthcoming paper.
- Glende, Carsten,Klein, Markus,Schmitt, Heimo,Erdinger, Lothar,Boche, Gernot
-
-
- Formulation of sulfonamides for treatment of endothelin-mediated disorders
-
Formulations of pharmaceutically-acceptable salts of thienyl-, furyl- and pyrrolyl-sulfonamides and methods for modulating or altering the activity of the endothelin family of peptides using the formulations are provided. In particular, formulations of so
- -
-
-
- Thiophenyl-, furyl-and pyrrolyl-sulfonamides and derivatives thereof that modulate the activity of endothelin
-
Thiophenyl-, furyl- and pyrrolyl-sulfonamides and methods for modulating or altering the activity of the endothelin family of peptides are provided. In particular, isoxazolyl-thiophenyl-sulfonamides, isoxazolyl-furyl-sulfonamides and isoxazolyl-pyrrolyl-sulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided.
- -
-
-
- THIENYL-, FURYL- AND PYRROLYL SULFONAMIDES AND DERIVATIVES THEREOF THAT MODULATE THE ACTIVITY OF ENDOTHELIN
-
Thienyl-, furyl-and pyrrolyl-sulfonamides and methods for modulating or altering the activity of the endothelin family of peptides are provided. In particular, N-(isoxazolyl)thienylsulfonamides, N-(isoxazolyl) furylsulfonamides and N-(isoxazolyl)pyrrolylsulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided.
- -
-
-
- SULFONAMIDES AND DERIVATIVES THEREOF THAT MODULATE THE ACTIVITY OF ENDOTHELIN
-
Sulfonamides and methods using these sulfonamides for inhibiting the binding of an endothelin peptide to an endothelin receptor by contacting the receptor with the sulfonamide are provided. Methods for treating endothelin-mediated disorders by administering effective amounts of one or more of these sulfonamides or prodrugs thereof that inhibit or increase the activity of endothelin are also provided. The sulfonamides have formula I: STR1 in which Ar 1 is a 3-or 5-isoxazolyl and Ar. sup.2 is selected from among alkyl, including straight and branched chains, aromatic rings, fused aromatic rings and heterocyclic rings, including 5-membered heterocycles with one, two or more heteroatoms and fused ring analogs thereof and 6-membered rings with one, two or more heteroatoms and fused ring analogs thereof. Ar 2 is preferably thiophenyl, furyl, pyrrolyl, naphthyl, and phenyl. Compounds in which Ar. sup.1 is a 4-halo-substituted isoxazole are more active than the corresponding alkyl-substituted compound and compounds in which Ar 1 is substituted at this position with a higher alkyl tend to exhibit greater affinity for ET B receptors than the corresponding lower alkyl-substituted compound.
- -
-
-