Publications by authors named "A A Sukhorukov"
The generation, interconversion, and reactivity of electrophilic species generated upon activation of nitroalkanes with protic acids (the Nef and Meyer reactions) were investigated by quantum-chemical calculations. ,-Bis(hydroxy)iminium (RC═N(OH)) and -oxoiminium (RC═N═O) cations were shown to be produced independently from -nitroalkanes, while -hydroxynitrilium cations (RC≡N-OH) were formed via nearly barrierless C-H bond cleavage in -oxoiminium cations. The -oxoiminium and -hydroxynitrilium cations whose formation is favored under highly acidic anhydrous conditions are strong electrophiles capable of reacting even with nonactivated arenes under ambient conditions.
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- * This study showcases the first-ever precise control of the emission angle for photon pairs generated in a nonlinear metasurface, achieving high-quality coincidence ratios in the emitted light.
- * A silicon dioxide grating on a nonlinear lithium niobate layer was used to facilitate this control, and the findings suggest potential for further improvements through modulation techniques, enhancing the capabilities of photon-pair sources.
Sum frequency generation (SFG) has multiple applications, from optical sources to imaging, where efficient conversion requires either long interaction distances or large field concentrations in a quadratic nonlinear material. Metasurfaces provide an essential avenue to enhanced SFG due to resonance with extreme field enhancements with an integrated ultrathin platform. In this work, we formulate a general theoretical framework for multi-objective topology optimization of nanopatterned metasurfaces that facilitate high-efficiency SFG and simultaneously select the emitted direction and tailor the metasurface polarization response.
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- A new two-step method for synthesizing aldols was developed using a conjugated nitroalkene and a sulfur ylide as key reactants, mimicking enolonium cations and α-carbinol anions, respectively.
- This technique allows for catalytic reductive cleavage of isoxazoline-oxides to produce aldols under mild conditions (room temperature and 1 atm hydrogen pressure).
- The method demonstrates efficiency in creating polysubstituted β-hydroxyketones that are challenging to make through traditional aldol reactions, enabling the selection of nitroalkene isomers for diverse aldol assembly.
, a new species in Bomi County, Xizang, China, was described and illustrated. In addition, , previously only known from Nepal and Bhutan, is newly recorded from Dingri County, Xizang, China. The phylogenetic placement of both species within the genus was analysed using nine plastid DNA markers (, , , , , , , , ).
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