An asymmetric approach toward chiral multicyclic spirooxindoles from isothiocyanato oxindoles and unsaturated pyrazolones by a chiral tertiary amine thiourea catalyst.
نویسندگان
چکیده
The first organocatalytic Michael-cyclization cascade reaction between isothiocyanato oxindoles and unsaturated pyrazolones has been developed. The multicyclic spiro[oxindole/thiobutyrolactam/pyrazolone] core structures containing three contiguous stereogenic centers, including two spiro quaternary centers, were prepared with excellent diastereo- (up to >20 : 1) and enantioselectivities (up to 99% ee).
منابع مشابه
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ورودعنوان ژورنال:
- Chemical communications
دوره 49 16 شماره
صفحات -
تاریخ انتشار 2013