Jiawang Liu  Ji Yang  Carolin Schneider  Robert Franke  Ralf Jackstell  Matthias Beller 《Angewandte Chemie (International ed. in English)》2020,59(23):9032-9040

For the first time, the monoalkoxycarbonylation of easily available 1,3‐diynes to give synthetically useful conjugated enynes has been realized. Key to success was the design and utilization of the new ligand 2,2′‐bis(tert‐butyl(pyridin‐2‐yl)phosphanyl)‐1,1′‐binaphthalene (Neolephos), which permits the palladium‐catalyzed selective carbonylation under mild conditions, providing a general preparation of functionalized 1,3‐enynes in good‐to‐high yields with excellent chemoselectivities. Synthetic applications that showcase the possibilities of this novel methodology include an efficient one‐pot synthesis of 4‐aryl‐4H‐pyrans as well as the rapid construction of various heterocyclic, bicyclic, and polycyclic compounds.  相似文献   

    

Sharafudheen Pottanam Chali  Bart Jan Ravoo 《Angewandte Chemie (International ed. in English)》2020,59(8):2962-2972

Carriers for intracellular delivery are required to overcome limitations of therapeutic agents such as low specificity, systemic toxicity, high clearance rate, and low therapeutic index. Nanocontainers comprised of an aqueous core and a polymer shell have received increasing attention because they readily combine stimuli response to improve intracellular payload release and surface modification to enhance selectivity towards the desired region of action. This Minireview summarizes the design and properties of polymer nanocontainers for intracellular delivery, classified according to the polymer architecture.  相似文献   

    

Meng Su  Feifei Qin  Zeying Zhang  Bingda Chen  Qi Pan  Zhandong Huang  Zheren Cai  Zhipeng Zhao  Xiaotian Hu  Dominique Derome  Jan Carmeliet  Yanlin Song 《Angewandte Chemie (International ed. in English)》2020,59(34):14234-14240

A key issue of micro/nano devices is how to integrate micro/nanostructures with specified chemical components onto various curved surfaces. Hydrodynamic printing of micro/nanostructures on three‐dimensional curved surfaces is achieved with a strategy that combines template‐induced hydrodynamic printing and self‐assembly of nanoparticles (NPs). Non‐lithography flexible wall‐shaped templates are replicated with microscale features by dicing a trench‐shaped silicon wafer. Arising from the capillary pumped function between the template and curved substrates, NPs in the colloidal suspension self‐assemble into close‐packed micro/nanostructures without a gravity effect. Theoretical analysis with the lattice Boltzmann model reveals the fundamental principles of the hydrodynamic assembly process. Spiral linear structures achieved by two kinds of fluorescent NPs show non‐interfering photoluminescence properties, while the waveguide and photoluminescence are confirmed in 3D curved space. The printed multiconstituent micro/nanostructures with single‐NP resolution may serve as a general platform for optoelectronics beyond flat surfaces.  相似文献   

    

Dr. Jan Schwabedissen  Pia C. Trapp  Dr. Hans-Georg Stammler  Prof. Dr. Norbert W. Mitzel  Zhuang Wu  Xianxu Chu  Prof. Dr. Xiaoqing Zeng 《ChemistryOpen》2020,9(9):913-920

Difluorothiophosphoryl isocyanate, F₂P(S)NCO was characterized with UV/vis, NMR, IR (gas and Ar-matrix), and Raman (liquid) spectroscopy. Its molecular structure was also established by means of gas electron diffraction (GED) and single crystal X-ray diffraction (XRD) in the gas phase and solid state, respectively. The analysis of the spectroscopic data and molecular structures is complemented by extensive quantum-chemical calculations. Theoretically, the C_s symmetric syn-conformer is predicted to be the most stable conformation. Rotation about the P−N bond requires about 9 kJ mol⁻¹ and the predicted existence of an anti-conformer is dependent on the quantum-chemical method used. This syn-orientation of the isocyanate group is the only one found in the gas phase and contained likewise in the crystal. The overall molecular structure is very similar in gas and solid, despite in the solid state the molecules arrange through intramolecular O⋅⋅⋅F contacts into layers, which are further interconnected by S⋅⋅⋅N, S⋅⋅⋅C and C⋅⋅⋅F contacts. Additionally, the photodecomposition of F₂P(S)NCO to form CO, F₂P(S)N, and F₂PNCO is observed in the solid Ar-matrix.  相似文献   

    

Thorsten Bies  Dr. Rudolf C. Hoffmann  Dr. Matthias Stöter  Dr. Adalbert Huber  Prof. Dr. Jörg J. Schneider 《ChemistryOpen》2020,9(12):1251-1263

Aluminum pigments were coated with Fe₂O₃ and CuO by solution-based thermal decomposition of the urea nitrate compounds hexakisureairon(III)nitrate and tetrakisureacopper(II)nitrate. The deposition process was optimized to obtain homogeneously coated aluminum pigments. The growth of the surface coatings was controlled by investigation with scanning electron microscopy, energy dispersive X-ray spectroscopy and static light scattering as well as infrared, X-ray diffraction and thermogravimetric analysis. The iron precursor showed an incomplete decomposition in solution, incorporating traces of urea molecules inside the coatings while the copper precursor showed complete dissociation accompanied by in situ formation of amine complexes. The amount of organic residues resulting from ligand fragments in the final oxide coatings could be reduced to 22 % for the iron oxide and 12 % for the copper oxide by further temperature treatment in solution (259 °C). Colorimetric investigations of the obtained pigments revealed an excellent hiding power, outperforming the pigments used in current state-of-the-art formulations.  相似文献   

    

Dr. Lenka Lorencova  Dr. Tomas Bertok  Dr. Aniko Bertokova  Veronika Gajdosova  Stefania Hroncekova  Dr. Alica Vikartovska  Dr. Peter Kasak  Dr. Jan Tkac 《ChemElectroChem》2020,7(9):1951-1951

  相似文献   

    

Gennady Pospelov  Walter Van Herck  Jan Burle  Juan M. Carmona Loaiza  Cline Durniak  Jonathan M. Fisher  Marina Ganeva  Dmitry Yurov  Joachim Wuttke 《Journal of Applied Crystallography》2020,53(1):262-276

  相似文献   

    

Andreas Schropp  Ralph Dhrmann  Stephan Botta  Dennis Brückner  Maik Kahnt  Mikhail Lyubomirskiy  Christina Ossig  Maria Scholz  Martin Seyrich  Michael E. Stuckelberger  Patrik Wiljes  Felix Wittwer  Jan Garrevoet  Gerald Falkenberg  Yakub Fam  Thomas L. Sheppard  Jan-Dierk Grunwaldt  Christian G. Schroer 《Journal of Applied Crystallography》2020,53(4):957-971

Ptychographic X‐ray imaging at the highest spatial resolution requires an optimal experimental environment, providing a high coherent flux, excellent mechanical stability and a low background in the measured data. This requires, for example, a stable performance of all optical components along the entire beam path, high temperature stability, a robust sample and optics tracking system, and a scatter‐free environment. This contribution summarizes the efforts along these lines to transform the nanoprobe station on beamline P06 (PETRA III) into the ptychographic nano‐analytical microscope (PtyNAMi).  相似文献   

    

Jonathan R. Thompson  Dr. Collin D. Davies  Dr. Jan Clausmeyer  Prof. Richard M. Crooks 《ChemElectroChem》2020,7(19):4108-4117

We report a new approach for forming ion depletion zones (IDZs) using intercalation reactions at an electrochemically controlled Prussian blue (PB) film. The experiments described here were performed using a microfluidic device, wherein a charged fluorophore in solution was used as a proxy to monitor IDZ formation. In the presence of K⁺, intercalation reactions proceed readily to form an IDZ, and thus enrich the fluorophore up to 37-fold. In the presence of the larger hydrated Li⁺ or tetrabutylammonium (TBA⁺) ions, however, ion intercalation proceeded less quickly than with K⁺. Slower ion intercalation resulted in a weaker IDZ and correspondingly lower enrichment factors of eight- and six-fold, respectively. These results are significant because they show that PB intercalation reactions selectively form an IDZ. Accordingly, we anticipate that these findings will lead to a better understanding and further interesting applications of intercalation materials like PB for efficient and selective enrichment and separations.  相似文献   

    

Jan Boschheidgen  Benjamin Klopsch  Anitha Thillaisundaram 《Mathematische Nachrichten》2020,293(7):1251-1258

  相似文献