A heterogeneous gold(I)-catalyzed ring expansion of unactivated alkynylcyclopropanes with sulfonamides leading to (E)-2-alkylidenecyclobutanamines

A novel, efficient, and practical heterogeneous gold(I)-catalyzed ring expansion of unactivated alkynylcyclopropanes to (E)-alkylidenecyclobutanamines in the presence of sulfonamides have been described.