Oxidative Asymmetric Aza-Friedel-Crafts Alkylation of Indoles with 3-Indolinone-2-carboxylates Catalyzed by a BINOL Phosphoric Acid and Promoted by DDQ
An asymmetric aza‐Friedel–Crafts alkylation reaction between indoles and indolenines that were derived in situ from 3‐indolinone‐2‐carboxylates has been developed by using 3,3′‐bis(triphenylsilyl)‐1,1′‐binaphthyl‐2,2′‐diyl hydrogen phosphate as a catalyst. The reaction proceeded under mild conditions and provided chiral indol‐3‐yl‐3‐indolinone‐2‐carboxylate derivatives in good yields with excellent
Organocatalytic Asymmetric Michael Addition of Oxindoles to Nitroolefins for the Synthesis of 2,2-Disubstituted Oxindoles Bearing Adjacent Quaternary and Tertiary Stereocenters
A bifunctional thiourea-catalyzed Michael addition of activated indolin-3-ones to nitroolefins has been developed. The synthetically useful 2,2-disubstituted indolin-3-one derivatives with vicinal chiral quaternary–tertiary stereocenters were obtained in high yields with excellent stereoselectivities. The adduct can be readily transformed into a structurally interesting heterocyclic architecture by
Organocatalytic Asymmetric α-Sulfenylation of 2-Substituted Indolin-3-ones: A Strategy for the Synthesis of Chiral 2,2-Disubstituted Indole-3-ones with S- and N-Containing Heteroquaternary Carbon Stereocenter
An organocatalytic asymmetric α-sulfenylation of 2-substituted indolin-3-ones with N-(alkylthio or arylthio)succinimides has been developed for the first time using Cinchona-derived squaramide as the catalyst. Various chiral 2,2-disubstituted indole-3-ones with S- and N-containing heteroquaternary carbon stereocenters were obtained with up to 98% yield and 99% ee.
Organocatalytic Enantioselective Michael Addition of 3-Indolinone-2-Carboxylates to Maleimides
作者:Suresh Yarlagadda、C. Ravikumar Reddy、Boora Ramesh、G. Ravi Kumar、B. Sridhar、B. V. Subba Reddy
DOI:10.1002/ejoc.201701670
日期:2018.3.22
The asymmetric conjugate addition of 2‐substituted 3‐indolinones to maleimides has been achieved by using a chiral bifunctional squaramide as an organocatalyst. This method provides easy access to 3‐indolinone‐2‐carboxylate‐succinimide adducts in high yields with exellent diastereo‐ and enantioselectivities.
Unexpected Insertion of Nitrogen into a C–C Bond: Access to 2,3-Disubstituted Quinazolinone Scaffolds
作者:Hui-Li Liu、Xiao-Tong Li、Heng-Zhi Tian、Xing-Wen Sun
DOI:10.1021/acs.orglett.1c01235
日期:2021.6.18
A novel, practical, highly efficient, and transition metal free nitrogeninsertion reaction for the synthesis of 2,3-disubstituted quinazolinone derivatives was developed. Diverse functionalized 3-indolinone-2-carboxylates and nitrosoarenes with a wide range of substituted nitrosobenzenes, nitrosopyridines, dibenzofuranyl, or dibenzothienyl nitroso compounds worked smoothly to give 2,3-disubstituted