A mesoporous aluminosilicate (Al-MCM-41) was found to be an effective heterogeneous catalyst for the reaction of both aldehydes and acetals with silylenolethers or ketene silylacetals to give the corresponding aldol adducts in moderate to high yields. The remarkable high catalytic activity of Al-MCM-41 over amorphous silica-alumina and aluminum-free mesoporous silicate was observed in the reaction
A cationic iridium complex [Ir(cod)2]SbF6 was found to be a new and efficient Lewis acid catalyst for Mukaiyama aldol and Mannich reactions. Aldehydes react smoothly with silyl enol ethers to give β-siloxy ketones in the presence of 0.5 mol % of [Ir(cod)2]SbF6. The reaction of N-alkyl arylaldimines with ketene silyl acetals in the presence of 5 mol % [Ir(cod)2]SbF6/P(OPh)3 gave β-amino esters. After
Polymer-supported PPh<sub>3</sub> as a reusable organocatalyst for the Mukaiyama aldol and Mannich reaction
作者:Satoru Matsukawa、Kazuki Fukazawa、Junya Kimura
DOI:10.1039/c4ra03394a
日期:——
An easily accessible and user-friendly polymer-supported phosphine PS-PPh3 catalyzes the aldol reaction of aldehydes and imines. A broad range of aldehydes and imines could be applied under mild conditions using 5–10 mol% PS-PPh3. PS-PPh3 was easily recovered and reused with minimal loss of activity.
Quaternary Ammonium Dendrimers as Lewis Base Catalysts for Mukaiyama–Aldol Reaction
作者:Tomoo Mizugaki、Casey E. Hetrick、Makoto Murata、Kohki Ebitani、Michael D. Amiridis、Kiyotomi Kaneda
DOI:10.1246/cl.2005.420
日期:2005.3
Surface-alkylated poly(propylene imine) dendrimer was treated with methyl iodide to afford quaternarized ammonium iodide dendrimer. The quaternarized dendrimer catalyzed the Mukaiyama–Aldol reaction of trimethylsilyl acetal with various aldehydes as a Lewis base in apolar toluene solvent.
Mischmetall, an alloy of the light lanthanides, has been used in a variety of organicreactions, either as a coreductant in samarium(II)-mediated reactions (Barbier and Grignard-type reactions, pinacoliccouplingreactions) or as the promoter of Reformatsky-type reactions. It has been also employed as the starting material for easy syntheses of lanthanide trihalides, the reactivity of which has been