Ruthenium clay catalyzed chemoselective hydrogenation of unsaturated esters, epoxides, sulfones and phosphonates
作者:Raluca Aldea、Howard Alper
DOI:10.1016/s0022-328x(97)00493-2
日期:1998.1
Ru-clays were prepared using montmorillonite–PPh2 or montmorillonite–bpy and RuCl3·H2O. The clays obtained were found to be effective catalysts for the reduction of unsaturatedesters, epoxides, sulfones and phosphonates.
Synthesis of<i>syn</i>and<i>anti</i>1,4-Diols by Copper-Catalyzed Boration of Allylic Epoxides
作者:Mariola Tortosa
DOI:10.1002/anie.201100613
日期:2011.4.18
Two sides of the same coin: Syn and anti 1,4‐diols have been synthesized through the regio‐ and diastereoselective CuI‐catalyzed boration of allylicepoxides (see scheme; pin=pinacolato, TES=triethylsilyl). In situ protection of the alcohol allows isolation of syn and anti 1,4‐silyloxyboronates. Monoprotected 1,4‐diols can be prepared by a one‐pot addition–protection–oxidation sequence.
Conjugate addition of α-alkoxystannanes via in situ transmetalation using catalytic CuCN
作者:Rama K. Bhatt、Jianhua Ye、J.R. Falck
DOI:10.1016/0040-4039(96)00710-1
日期:1996.5
CatalyticCuCN mediates the in situ transrnetalation of α-thionocarbamoyl stannanes and subsequent conjugateaddition to α,β-unsaturated carbonyls in the presence of chlorotrimethlysilane at or a little above room temperature.
A process of making racemic [2S*[R*[R*[R*]]]] and [2R*[S*[S*[S*]]]]-(±)α,α′-[iminobis(methylene)]bis[6-fluoro-3,4-dihydro-2H-1-benzopyran-2-methanol] of the compound of the formula (I)
and its pure [2S*[R*[R*[R*]]]]- and [2R*[S*[S*[S*]]]]-enantiomer compounds and pharmaceutically acceptable salts thereof.
Hyperaromatic Stabilization of Arenium Ions: Cyclohexa- and Cycloheptadienyl Cations—Experimental and Calculated Stabilities and Ring Currents
作者:David A. Lawlor、David E. Bean、Patrick W. Fowler、James R. Keeffe、Jaya Satyanarayana Kudavalli、Rory A. More O’Ferrall、S. Nagaraja Rao
DOI:10.1021/ja2071626
日期:2011.12.14
in stabilities of the two ions. Interpretation of this difference in terms of hyperconjugative aromaticity is supported by the effect of benzannelation in reducing pK(R) for the benzeniumion: from -2.6 down to -3.5 for the 1H-naphthalenium and -6.0 for the 9H-anthracenium ions, respectively. MP2/6-311+G** and G3MP2 calculations of hydride ion affinities of benzeniumions show an order of stabilities