Jun-Bing Lin, Xi-Na Cheng, Xiao-Dong Tian, Guo-Qiang Xu, Yong-Chun Luo and Peng-Fei Xu
RSC Adv., 2018,8, 15444-15447
DOI:
10.1039/C8RA02009D,
Paper
Open Access Learn more..A C1-symmetric N-heterocyclic carbene (NHC)-catalysed activation of isatin-derived enals under oxidative conditions was achieved. The in situ generated α,β-unsaturated acyl azolium species was efficiently trapped by 1,3-dicarbonyl compounds via a Michael addition/spiroannualtion cascade, delivering a series of synthetically important spirooxindole δ-lactones with up to 96% enantioselectivity.
