In this work, six novelaxiallyunfixed biaryl‐based water‐compatible bifunctionalorganocatalysts were designed and synthesized for the organocatalytic access to a variety of 3‐alkyl‐3‐hydroxy‐2‐oxindole derivatives via aldol reactions in water. Organocatalyzed by 5a, the direct aldol reactions of isatins with enolisable ketones underwent readily in water, furnishing the structurally diverse 3‐al
The synthesis and application of a newly designed C2-symmetric chiral bifunctional triamine family (C2-CBT) is reported. These enantiopure chiral triamine scaffolds can be accessed in multigram amounts from simple amino acids while avoiding chromatographic purification. As a proof of principle, C2-CBT has been studied in the aldol reaction of cyclic ketones with isatins, with the target tertiary alcohols
Enantioselectivealdolreactions of various isatins with ketones using newly designed amino amide organocatalysts were found to provide chiral 3-substituted 3-hydroxy-2-oxindoles in good to excellent yields and with excellent stereoselectivities (up to 99 %, up to 98 % ee, syn/anti = 99:1); one catalyst, 3i, proved particularly successful. One of the resulting oxindoles, 3-hydroxy-3-(2-oxocyclohexyl)-2-indolinone
EnantioselectiveAldol Reaction Between Isatins and Cyclohexanone Catalyzed by Amino Acid Sulphonamides
作者:Jun Wang、Qi Liu、Qing Hao、Yanhua Sun、Yiming Luo、Hua Yang
DOI:10.1002/chir.22433
日期:2015.4
Sulphonamides derived from primary α‐aminoacid were successfully applied to catalyze the aldolreaction between isatin and cyclohexanone under neat conditions. More interestingly, molecular sieves, as privileged additives, were found to play a vital role in achieving high enantioselectivity. Consequently, high yields (up to 99%) along with good enantioselectivities (up to 92% ee) and diastereoselectivities
Highly enantioselective synthesis of 3-cycloalkanone-3-hydroxy-2-oxindoles, potential anticonvulsants
作者:Monika Raj、Nagarathanam Veerasamy、Vinod K. Singh
DOI:10.1016/j.tetlet.2010.02.082
日期:2010.4
Highly enantioselective catalytic synthesis of 3-cycloalkanone-3-hydroxy-2-oxindoles was achieved by using primary-tertiary diamine-Brønsted acid catalyst in both organic medium and aqueous medium. The products, thus obtained act as potentialanticonvulsants.