Wenyao Wang, Shiqiang Wei, Xiaoze Bao, Shah Nawaz, Jingping Qu and Baomin Wang
Org. Biomol. Chem., 2021,19, 1145-1154
DOI:
10.1039/D0OB02423F,
Paper
An asymmetric [3 + 2] annulation reaction of 4-isothiocyanato pyrazolones with alkynyl ketones in the presence of an organic catalyst derived from a cinchona alkaloid under mild conditions is realized. This protocol provides unprecedented expeditious access to a wide range of optically active spiro[pyrroline–pyrazolones] with various electronic properties in high yields with good to excellent enantioselectivities.
![Graphical abstract: Enantioselective [3 + 2] annulation of 4-isothiocyanato pyrazolones and alkynyl ketones under organocatalysis](/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=D0OB02423F "Graphical abstract")
