Now with nickel: [3C+2C+2C] cycloadditions involving non-activated alkylidenecyclopropanes provide a practical entry to a variety of interesting 6,7-fused bicyclic systems (see scheme; cod=1,5-cyclooctadiene). DFT calculations, combined with experimental data, suggest that the catalytic cycle involves the initial formation of 1-alkylidenenickelacyclobutane intermediates, such as 1.