<i>Z</i>‑Stereoselective Aza-Peterson Olefinations with Bis(trimethylsilane) Reagents and Sulfinyl Imines

Highly stereoselective aza-Peterson olefinations from bench-stable α,α-bis­(trimethylsilyl)­toluene reagents and N-substituted imines have been achieved using TMSO^–/Bu₄N⁺ as Lewis base activator in THF. Remarkably, and for the first time, <i>N</i>-<i>t</i>-butanesulfinyl imines were utilized for the synthesis of <i>Z</i>-stilbenes with excellent selectivities, while <i>N</i>-aryl imines generated <i>E</i>-stilbenes under identical reaction conditions. The protocol proved general for numerous examples with low molecular weight byproducts formed. The origin of the Z-selectivity is proposed to be a result of diastereoselective addition to <i>N</i>-<i>t</i>-butanesulfinyl imines followed by <i>syn</i>-elimination of an in situ formed hypervalent silicate

Silyloxide-Promoted Diastereoselective Addition of Aryl and Heterocyclic Trimethylsilanes to <i>N</i>-<i>tert</i>-Butanesulfinylimines

The addition of a broad variety of substituted aromatic and heterocyclic silanes to chiral <i>N</i>-<i>tert-</i>butanesulfinylimines has been achieved providing 1,1-diaryl and diheterocyclic substituted sulfinamides with excellent diastereoselectivity in all cases. Employing Me₃SiO^–/Bu₄N⁺ as the Lewis base activator for silicon allowed a general procedure for all silane reagents, including the less reactive aromatic derivatives. Evidence that the diastereoselective additions occur via an open transition state is presented

Stereoselective Alkyne Hydrohalogenation by Trapping of Transfer Hydrogenation Intermediates

A catalytically generated vinylcopper complex, the reactive intermediate of a copper­(I)-catalyzed alkyne transfer hydrogenation, can be trapped by commercially available halogen electrophiles. In this manner, internal alkynes can stereoselectively be hydrohalogenated to the corresponding vinyl chlorides, bromides, and iodides

Stereoselective Alkyne Hydrohalogenation by Trapping of Transfer Hydrogenation Intermediates

A catalytically generated vinylcopper complex, the reactive intermediate of a copper­(I)-catalyzed alkyne transfer hydrogenation, can be trapped by commercially available halogen electrophiles. In this manner, internal alkynes can stereoselectively be hydrohalogenated to the corresponding vinyl chlorides, bromides, and iodides

Expression of mRNAs for gluconeogenic enzymes.

<div><p>qPCR analysis showing the levels of relative expression of mRNAs for different gluconeogenic enzymes in liver and kidney tissues of singhi catfish following exposure to environmental hypertonicity at different time intervals. Values are plotted as mean ± S.E.M. (n = 5)</p> <p>^c : <i>P</i> value significant at <0.001 level, compared to respective controls (Student’s <i>t</i>-test)</p></div

Zonal localization of PEPCK.

<p>Immunocytochemical analysis showing the localized expression of PEPCK in liver and kidney tissues of singhi catfish following exposure to hypertonic environment at different time intervals. Representative pictures of three independent experiments are shown. Nucleus – blue (DAPI); PEPCK – red (cy3). Scale bar: 55 µm.</p

Expression pattern of PEPCK enzyme protein.

<div><p>Western blot analysis showing changes in the levels of expression of PEPCK enzyme protein in liver (L) and kidney (K) of singhi catfish following exposure to environmental hypertonicity at different time intervals. (A) A representative plot of 5 individual experiments. GAPDH was taken as a protein loading control. (B) Densitometric analysis showing the fold increase of PEPCK protein concentration in treated fish compared to respective controls. Values are plotted as mean ± S.E.M. (n = 5).</p> <p>^c :P value significant at <0.001 level compared to respective controls (Student’s <i>t</i>-test).</p></div

Zonal localization of G6Pase.

<p>Immunocytochemical analysis showing the localized expression of G6Pase in liver and kidney tissues of singhi catfish following exposure to hypertonic environment for different time intervals. Representative pictures of three independent experiments are shown. Nucleus – blue (DAPI); G6Pase – red (cy3). Scale bar: 55 µm.</p

Zonal localization of FBPase.

<p>Immunocytochemical analysis showing the localized expression of FBPase in liver and kidney tissues of singhi catfish following exposure to hypertonic environment at different time intervals. Representative pictures of three independent experiments are shown. Nucleus – blue (DAPI); FBPase – red (cy3). Scale bar: 55 µm.</p

sj-docx-1-pie-10.1177_09544089221139102 - Supplemental material for Experimental and theoretical analyses of material removal in poppet valve magnetorheological finishing

Supplemental material, sj-docx-1-pie-10.1177_09544089221139102 for Experimental and theoretical analyses of material removal in poppet valve magnetorheological finishing by Manjesh Kumar, Chandan Kumar, Amit Kumar, Debashish Gogoi and Manas Das in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p