Fig. 6: Control experiments.
From: Asymmetric formal C–C bond insertion into aldehydes via copper-catalyzed diyne cyclization

a Isolation of 1,3-dioxolane intermediate. b Reaction of 1,3-dioxolane intermediate in standard conditions.
From: Asymmetric formal C–C bond insertion into aldehydes via copper-catalyzed diyne cyclization

a Isolation of 1,3-dioxolane intermediate. b Reaction of 1,3-dioxolane intermediate in standard conditions.