Abstract

Organocatalytic annulations between allenes and bisnucleophiles represent one of the most convenient routes to various carbocycles and heterocycles. However, most examples are limited to the formation of five- and six-membered rings, probably owing to relatively easy handling of short-chained biselectrophiles. Here we report long-chained α-allyl allenoate-derived 1,6-biselectrophiles for the first time, enabling a phosphine catalyzed [6 + 1] annulation with readily available 1,1-bisnucleophilic reagents. The reaction proceeds