Synthesis of 3,3-disubstituted oxindoles by one-pot integrated Brønsted base-catalyzed trichloroacetimidation of 3-hydroxyoxindoles and Brønsted acid-catalyzed nucleophilic substitution reaction
作者:Cyril Piemontesi、Qian Wang、Jieping Zhu
DOI:10.1039/c2ob27196f
日期:——
Treatment of 3-hydroxyoxindoles with trichloroacetonitrile (1.3 equiv.) and a catalytic amount of DBU (0.1 equiv.) followed by addition of nucleophiles (1.5 equiv.) and diphenylphosphoric acid (0.2 equiv.) afforded the 3,3-disubstituted oxindoles in good to excellent yields. DFT computations supported the notion that the reaction went through the 1-alkyl-2-oxo-2H-indol-1-ium intermediate.
An Efficient Approach to the Total Synthesis of Ammosamide B
作者:Sheng-Wei Yang、Chun-Meng Wang、Kai-Xiang Tang、Jin-Xin Wang、Li-Ping Sun
DOI:10.1002/ejoc.201501560
日期:2016.2
A new approach for the total synthesis of ammosamide B was realized. The strategy is based on an intermolecular Pd-catalyzed N-arylation of 4-chloro-1-methylindoline-2,3-dione (2), which enables construction of the key pyrroloquinoline skeleton precursor 6 within three steps in an overall yield of 80 %. The ammosamide B total synthesis is achieved in 12 simple transformations by starting from a commercially