69833-26-7Relevant articles and documents
Organocatalytic and enantioselective [4+2] cyclization between hydroxymaleimides and: Ortho -hydroxyphenyl para -quinone methide-selective preparation of chiral hemiketals
Xiang, Min,Li, Chen-Yi,Song, Xiang-Jia,Zou, Ying,Huang, Zhi-Cheng,Li, Xia,Tian, Fang,Wang, Li-Xin
supporting information, p. 14825 - 14828 (2020/12/07)
A cinchona alkaloid squaramide promoted enantioselective [4+2] cyclization between hydroxymaleimides and ortho-hydroxyphenyl p-QMs has been disclosed, and a wide range of chiral hemiketals containing chromane and succinimide frameworks with two adjacent quaternary stereogenic centers have been prepared for the first time with excellent results (up to 99% yield, up to 99?:?1 dr, up to >99% ee) under mild conditions. This journal is
Organocatalytic Asymmetric Annulation between Hydroxymaleimides and Nitrosoarenes: Stereoselective Preparation of Chiral Quaternary N-Hydroxyindolines
Yang, Yu,Ren, Hong-Xia,Chen, Feng,Zhang, Zheng-Bing,Zou, Ying,Chen, Chao,Song, Xiang-Jia,Tian, Fang,Peng, Lin,Wang, Li-Xin
supporting information, p. 2805 - 2808 (2017/06/07)
An unusual and highly effective asymmetric annulation of nitrosoarenes with hydroxymaleimides catalyzed by a chiral bifunctional amine squaramide catalyst has been disclosed. A wide range of highly fused chiral N-hydroxyindolines with two consecutive quaternary stereocenters and multifunctional groups were directly and effectively prepared in excellent yields (up to >99%) with complete regioselective cyclization and excellent stereoselectivities (up to >99:1 dr and >99% ee). The efficiency and potentials of the new reaction and the target chiral entities were well demonstrated by delicate transformations into a series of new chiral indolines.
Bis(salicylaldehyde)ethylenedi-iminecobalt(II)-catalysed Oxidation of Aromatic Amins with Oxygen
Benedini, Francesca,Galliani, Guido,Nali, Micaela,Rindone, Bruno,Tollari, Stefano
, p. 1963 - 1968 (2007/10/02)
N-n-Butylanilines undergo N-dealkylation to give a primary amine and butyrylaldehyde by oxidation with oxygen in the presence of bis(salicylaldehyde)ethylenedi-iminecobalt(II) (CoIIsalen) as a catalyst.High conversions are obtained with high catalyst concentrations and low / ratios (r).Inspection of the effect of catalyst and substrate concentrations on initial reaction rates (Vin) shows poor sensitivity to the electronic effect of the nuclear substituent.Some anilines give azo derivatives at a lower rate in the same conditions.