Highly Efficient Enantioselective Construction of Bispirooxindoles Containing Three Stereocenters through an Organocatalytic Cascade Michael-Cyclization Reaction
作者:Hao Wu、Li-Li Zhang、Zhi-Qing Tian、Yao-Dong Huang、Yong-Mei Wang
DOI:10.1002/chem.201203221
日期:2013.1.28
Bispirooxindole derivatives containing three stereocenters, including two spiro quaternary centers, were synthesized in a high‐yielding, atypically rapid, and stereocontrolled cascade Michael–cyclization reaction between methyleneindolinones and isothiocyanato oxindoles catalyzed by a bi‐ or multifunctional organocatalyst. Mild conditions were used to construct bispirooxindoles with excellent enantio‐
An efficient asymmetric dearomative [3+2] cycloadditionreaction of 2‐nitroindoles and 2‐nitrobenzothiophenes with 3‐isothiocyanato oxindoles was developed by using a chiral Zn(OTf)2/bis(oxazoline) complex as a catalyst. With the developed protocol, a range of enantioenriched complex heterocyclic compounds containing three contiguous stereocenters, one of which is spirocyclic center, could be obtained
Organocatalytic [3+2] Cycloadditions of Barbiturate-Based Olefins with 3-Isothiocyanato Oxindoles: Highly Diastereoselective and Enantioselective Synthesis of Dispirobarbiturates
Catalyzed by a Cinchona‐based thiourea, the [3+2] cycloadditions of barbiturate‐based olefins with 3‐isothiocyanatooxindoles proceeded readily, and furnished dispirobarbiturates in excellent chemical yields with excellent diastereo‐ and enantioselectivities. The absolute configuration of dispirobarbiturates was firmly confirmed by an X‐ray single crystal structure analysis. A reaction mechanism was
Organocatalytic asymmetric synthesis of trans -configured trispirooxindoles through a cascade Michael-cyclization reaction
作者:Chaoling Wu、Linhai Jing、Dabin Qin、Mingxing Yin、Qiuzuo He
DOI:10.1016/j.tetlet.2016.05.056
日期:2016.6
stereoselective Michael-cyclization reaction of 3-isothiocyanato oxindoles to cyclic methyleneindolinones has been described. The protocol provides a facile and efficient access to chiral trans-configured trispirooxindoles containing two quaternary stereocenters in good yields (up to 89%) with good diastereoselectivities (up to 90:10) and high enantioselectivities (up to 94% ee) under mild conditions
Highly Enantioselective Organocatalytic Michael Addition/Cyclization Cascade Reaction of Ylideneoxindoles with Isothiocyanato Oxindoles: A Formal [3+2] Cycloaddition Approach to Optically Active Bispirooxindole Derivatives
A formal [3+2] cycloaddition involving the organocatalytic asymmetric Michael addition/cyclization cascade reaction of ylideneoxindoles with isothiocyanato oxindoles was developed. This method allows efficient and rapid synthesis of highly functionalized bispirooxindole products bearing three contiguous stereogenic centers with two quaternary stereocenters in almost quantitative yields with extremely