Table 1. Intramolecular Alkene [2π + 2π] Cycloaddition Performance of Bis(imino)pyridine Iron and Cobalt Dinitrogen Complexes.

^aIsolated yields.

^bThe reaction was run at 0.2 M in C₆D₆, and the yield was determined by ¹H NMR analysis using diiodomethane as an internal standard.

^c2.5 mol % [Fe] was added to the 1 mol % experiment.

^dStoichiometric C–O bond cleavage with respect to [Fe].

^eA 22% yield of 3-methyl-4-methylenetetrahydrofuran was also dectected.

^fThe diastereomeric ratio was determined by ¹H NMR analysis; the major diastereomer is shown.

^gThe reaction was run at 50 °C.