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1.
Immobilized scandium triflate [Sc(OTf)3] in ionic liquids has been found to be an extremely efficient and recyclable catalyst for the thioacetalization and transthioacetalization of both aromatic and aliphatic aldehydes. Significant rate acceleration and chemoselectivity was achieved by employing this catalytic system. 相似文献
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Palladium-catalyzed carboxamidation reaction and aldol condensation reaction cascade are very useful for the synthesis of various ABC ring substituted fused isoquinolinones. 相似文献
3.
Sandeep Goyal Anang Pal Mangilal Chouhan Mukesh Gangar Sharad Sarak Vipin A. Nair 《Tetrahedron letters》2017,58(4):346-348
An efficient strategy for a one-pot, single step synthesis of β-lactams employing an imidazolidinone based chiral auxiliary with various aldimines via asymmetric Mannich-type reaction has been described. 相似文献
4.
A simple and very efficient gas jet levitation technique for levitating inertial confinement fusion (ICF) targets has been
developed. A low velocity gas jet through diverging nozzle generates precisely controlled low Reynolds number flow pattern,
capable of levitating polymer microballoons up to 2500 μm diameter. Different shaped diverging nozzle are investigated, satisfactory
levitation is achieved with simple conical shapes. With this setup microballoon can be levitated for hours with excellent
stability, continuous rotation and at the desired height (reproducible with in less than 100 μm). The height of stabilization
depends upon cone angle of diverging nozzle and velocity of levitating gas. This technique is very robust and highly insensitive
to external disturbances like nonuniform temperature fields and vibrations.
This setup is very economical to fabricate, easy to operate and can be used efficiently in various spray coating application
involving plastic and metallic layers on microballoons. 相似文献
5.
C. Guénaut G. Bollen S. Chouhan F. Marti D. J. Morrissey D. Lawton J. Ottarson G. K. Pang S. Schwarz B. M. Sherrill M. Wada A. F. Zeller 《Hyperfine Interactions》2006,172(1-3):35-40
Permanent electric dipole moments (EDMs) violate parity and time-reversal symmetry. Within the Standard Model (SM), they require
CP violation and are many orders of magnitude below present experimental sensitivity. Many extensions of the SM predict much
larger EDMs, which are therefore an excellent probe for the existence of ‘new physics.’ So far only electrically neutral systems
were used for sensitive searches of EDMs. Several techniques, based on storing fast particles in a magnetic storage ring,
are being developed to probe charged particles for an EDM. With the introduction of these novel experimental methods, high
sensitivity for charged systems, in particular light nuclei, is within reach.
The author represents the Storage Ring EDM Collaboration. 相似文献
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One‐pot regioselective benzylation of pyrroles and indoles using zirconium tetrachloride is discussed. This has been achieved by in‐situ generation of di(1H‐pyrrol‐1‐yl)zirconium(IV) chloride and di(1H‐indol‐1‐yl)zirconium(IV) chloride. It was observed that benzylation reactions of these complexes using n‐BuLi occurred at C‐2 position for pyrrole and C‐3 for indole. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
8.
A mild and rapid one‐pot process for Reformatsky and Barbier reactions using a catalytic quantity of zirconocene dichloride (Cp2ZrCl2) as a promoter and zinc as a terminal reductant at room temperature in dimethyl formamide was developed. The protocol has wide substrate suitability and afforded the desired 3‐substituted‐3‐hydroxyindolin‐2‐ones from istains in good yields and short reaction time. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
9.
Dr. M. D. Shahjahan Dr. Takuya Okamoto Dr. Lata Chouhan Dr. Bhagyashree Mahesha Sachith Prof. Dr. Narayan Pradhan Prof. Dr. Hiroaki Misawa Prof. Dr. Vasudevanpillai Biju 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215947
Halide perovskites are materials for future optical displays and solar cells. Electron donor-acceptor perovskite heterostructures with distinguishing halide compositions are promising for transporting and harvesting photogenerated charge carriers. Combined e-beam lithography and anion exchange are promising to develop such heterostructures but challenging to prepare multiple heterojunctions at desired locations in single crystals. We demonstrate swift laser trapping-assisted band gap engineering at the desired locations in MAPbBr3 microrods, microplates, or nanocrystal thin films. The built-in donor-acceptor double and multi-heterojunction structures let us transport and trap photogenerated charge carriers from wide-band gap bromide to narrow-band gap iodide domains. We discuss the charge carrier transport and trapping mechanisms from the viewpoints of engineered bands and band continuity. This work offers a convenient method for designing single-, double- and multi-heterojunction donor-acceptor halide perovskites for photovoltaic, photonic, and electronic applications. 相似文献
10.
Magnetic nanoparticle-supported proline ligand was prepared and used for the CuI catalyzed Ullmann-type coupling reactions of aryl/heteroaryl bromides with various nitrogen heterocycles to form the corresponding N-aryl products in good to excellent yields; furthermore, this magnetic nanoparticle-supported proline ligand could be readily separated using an external magnet and reused without significant loss of activity. 相似文献