Fig. 1: Catalytic [3 + 2]- and formal [1 + 2 + 2]-cycloadditions.
From: Asymmetric formal [1 + 2 + 2]-cycloaddition of diazoamides with enamines and carbonyl compounds
![Fig. 1: Catalytic [3 + 2]- and formal [1 + 2 + 2]-cycloadditions.](http://media.springernature.com/full/springer-static/image/art%3A10.1038%2Fs41467-025-65612-3/MediaObjects/41467_2025_65612_Fig1_HTML.png?as=webp)
a General protocols for the catalytic [3 + 2]- and [1 + 2 + 2]-cycloadditions. b Catalytic [3 + 2]-cycloaddition of in situ formed carbonyl ylide with alkene. c Interception transformations of in situ formed zwitterionic intermediate & our hypothesis. d This work: formal [1 + 2 + 2]-cycloaddition via interception of zwitterionic intermediate with carbonyl compound.
