First example of quinine-squaramide catalyzed enantioselective addition of diphenyl phosphite to ketimines derived from isatins
作者:Jimil George、B. Sridhar、B. V. Subba Reddy
DOI:10.1039/c3ob42026d
日期:——
A highlyenantioselective addition of diphenyl phosphite to ketimines derived from isatins has been achieved using a bifunctional organocatalyst, quinine-derived squaramide catalyst. This method works efficiently with several ketimines to produce the corresponding 3-amino-2-oxoindolin-3-yl-phosphonates in excellent yields with high enantioselectivity (up to 98% ee).
A highly enantioselective addition of diphenylphosphite to ketimines derived from isatins has been developed employing bifunctional thiourea-tertiary amine organocatalysts. A variety of isatins derived ketimines react well with diphenylphosphite in the presence of Cinchona-derived thiourea (epiCDT) to provide biologically important chiral 3-substituted 3-amino-2-oxindoles (3a–l) in good yield (up
Enantioselective addition of diphenyl phosphonate to ketimines derived from isatins catalyzed by binaphthyl-modified organocatalysts
作者:Hee Seung Jang、Yubin Kim、Dae Young Kim
DOI:10.3762/bjoc.12.149
日期:——
Chiral binaphthyl-modified squaramide-catalyzed enantioselectiveaddition of diphenyl phosphonate to ketimines derived from isatins has been achieved. This method affords practical and efficient access to chiral 3-amino-3-phosphonyl-substituted oxindole derivatives in high yields with excellent enantioselectivities (up to 99% ee).