An asymmetric approach toward chiral multicyclic spirooxindoles from isothiocyanato oxindoles and unsaturated pyrazolones by a chiral tertiary amine thiourea catalyst
作者:Qiao Chen、Jinyan Liang、Shoulei Wang、Dong Wang、Rui Wang
DOI:10.1039/c3cc38386e
日期:——
The first organocatalytic Michael-cyclization cascade reaction between isothiocyanato oxindoles and unsaturated pyrazolones has been developed. The multicyclic spiro[oxindole/thiobutyrolactam/pyrazolone] core structures containingthreecontiguous stereogenic centers, including twospiroquaternarycenters, were prepared with excellent diastereo- (up to >20 : 1) and enantioselectivities (up to 99%