10.1021/acs.orglett.7b02161.s001 Wenjun Li Wenjun Li Ming Lang Ming Lang Jian Wang Jian Wang Access to Cyclobutadienes via an Organocatalytic Dienamine–Iminium–Allenamine Cascade Approach American Chemical Society 2017 Organocatalytic dienamine Access Approach Cyclobutadiene ynal substrate scope mechanism aldehyde cyclobutadiene Cascade organocatalytic route Dienamine cascade 2017-09-01 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Access_to_Cyclobutadienes_via_an_Organocatalytic_Dienamine_Iminium_Allenamine_Cascade_Approach/5319511 A new organocatalytic route to cyclobutadienes from α,β-unsaturated aldehydes and ynals is described. This protocol allows a broad substrate scope and mild conditions. Furthermore, a proposed mechanism of a dienamine–iminium–allenamine cascade process is discussed.