Synfacts 2017; 13(11): 1199
DOI: 10.1055/s-0036-1591365
Organo- and Biocatalysis
© Georg Thieme Verlag Stuttgart · New York

Cyclobutadienes via an Organocascade

Benjamin List
Oleg Grossmann
Li W. Lang M. Wang J. * Tsinghua University, Beijing, P. R. of China
Access to Cyclobutadienes via an Organocatalytic Dienamine–Iminium–Allenamine Cascade Approach.

Org. Lett. 2017;
19: 4564-4567
Further Information

Publication History

Publication Date:
19 October 2017 (online)



The Wang group reports an organocatalytic [2+2] cycloaddition between α,β-unsaturated aldehydes and ynals. This reaction is catalyzed by secondary amines and generates cyclo-butadienes in high yields under mild conditions.



The authors suggest that the reaction follows a dienamine–iminium–allenamine cascade sequence furnishing cyclobutadienes as products. Typically high temperatures are required for the synthesis of cyclobutadienes. This method requires only room temperature, hence overcoming a limitation of previous methods.