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
Condensation of trimethylsilylacetonitrile or ethyltrimethylsilyacetate with benzaldehyde, in the presence of dried alcali metalfluorides in heterogeneous media under microwaves leads readily to β-trimethylsilyloxynitrile or ester according to a Reformatsky type reaction. The later products could be hydrolyzed and dehydrated on the wet inorganic salt to give the corresponding alkenes.
Brønsted‐Acid‐Catalyzed One‐Pot Synthesis of β,β‐Diaryl Esters: Direct Regioselective Approach to Diverse Arrays of 3‐Aryl‐1‐indanone Cores
作者:Pragya Sharma、Neha Taneja、Sanjay Singh、Chinmoy K. Hazra
DOI:10.1002/chem.202202956
日期:2023.1.9
Three-component, solvent-dependent, Brønsted-acid-catalyzed reaction of benzaldehydes, silyl enolates and arene nucleophiles has been developed for the synthesis of potential drug candidate 3-aryl-1-indanones. This reaction features the formation of three C−C bonds, high regioselectivity in a one-pot strategy, broad substrate generality, facile scalability, high functional group tolerance and viable
sec-Benzyl azides were efficiently prepared by bismuth(III)-catalyzed direct azidation of sec-benzyl alcohols. The reaction was applied to a variety of substrates to provide the desired products in up to 99% yield within a short reaction time.
The Mukaiyama Aldol and Mukaiyama–Michael Reactions Promoted by Commercially Available Molecular Sieves
The Mukaiyama aldol reaction of silyl ketene acetals with aldehydes has been effected by using commercially available 4 angstrom molecular sieves (4 angstrom MS) as a promoter. Various silyl ketene acetals and silyl enol ethers have been shown to be effective nucleophiles for this reaction. For the first time, it has been found that 4 angstrom MS can promote the Mukaiyama Michael addition reactions of silyl ketene acetals to alpha,beta-enones.