NHC-catalyzed enantioselective [2 + 2] and [2 + 2 + 2] cycloadditions of ketenes with isothiocyanates

Xiao-Na Wang; Li-Tao Shen; Song Ye

doi:10.1021/ol202688h

NHC-catalyzed enantioselective [2 + 2] and [2 + 2 + 2] cycloadditions of ketenes with isothiocyanates

Org Lett. 2011 Dec 16;13(24):6382-5. doi: 10.1021/ol202688h. Epub 2011 Nov 15.

Authors

Xiao-Na Wang¹, Li-Tao Shen, Song Ye

Affiliation

¹ Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

PMID: 22085031
DOI: 10.1021/ol202688h

Abstract

The enantioselective N-heterocyclic carbene-catalyzed formal [2 + 2] and [2 + 2 + 2] cycloaddition of ketenes and isothiocyanates were developed. Reaction with N-aryl isothiocyanates at room temperature favors the [2 + 2] cycloaddition, while reaction with N-benzoyl isothiocyanates at -40 °C favors the [2 + 2 + 2] cycloaddition.