Iron(III) Chloride as a Water-Compatible Lewis Acid for Diastereoselective Aldol Reactions in Water in the Presence of a Surfactant
作者:Naohiro Aoyama、Kei Manabe、Shu Kobayashi
DOI:10.1246/cl.2004.312
日期:2004.3
Diastereoselective aldol reactions of various aldehydes with silicon enolates in water have been successfully carried out using iron(III) chloride and a surfactant. Contrary to previous understandi...
Iron- and Bismuth-Catalyzed Asymmetric Mukaiyama Aldol Reactions in Aqueous Media
作者:Taku Kitanosono、Thierry Ollevier、Shū Kobayashi
DOI:10.1002/asia.201301149
日期:2013.12
asymmetric Mukaiyamaaldolreactions of silicon enolates with aldehydes catalyzed by chiral FeII and BiIII complexes. Although previous reactions often required relatively harsh conditions, such as strictly anhydrous conditions, very low temperatures (−78 °C), etc., the reactions reported herein proceeded in the presence of water at 0 °C. To find appropriate chiral water‐compatible Lewisacids for the
STANNOUS TRIFLATE: A NEW ALDOL REACTION VIA DIVALENT TIN ENOLATES
作者:Teruaki Mukaiyama、Rodney. W. Stevens、Nobuharu Iwasawa
DOI:10.1246/cl.1982.353
日期:1982.3.5
Divalent tin enolates formed from stannous triflate and ketones react with carbonyl compounds under mild conditions to give the corresponding aldol products in good yields. In the case of cross-cou...
aldol reactions in water using a catalytic amount of diarylborinic acid have been developed. The reactions proceeded smoothly in the presence of a small amount of an anionic surfactant and a Brønsted acid. Water was the most suitable solvent, and organic solvents such as ether and dichloromethane were ineffective in this system. Use of bis(4-trifluoromethylphenyl)borinic acid gave high catalytic activity
Cu(OTf)2 was found to be a stable Lewis acid in aqueous media and to activate carbonyl compounds effectively. Aldol reactions of silyl enol ethers with aldehydes and allylation reactions of tetraallyltin with carbonyl compounds proceeded smoothly in aqueous media, to afford the corresponding adducts in high yields. In addition, the catalyst could be easily recovered quantitatively after the reaction