The role of cyclopentadienyl versus indenyl in Mo(II) spirodiene complexes reactivity: A DFT mechanistic study

For indenyl, the spirodiene complex rearranges to the monocarbonyl species with an activation barrier of 21 kcal mol−1 (reaction on the right) whereas for cyclopentadienyl the analogous pathway requires 35 kcal mol−1(reaction on the left). These DFT mechanistic results corroborate the reactivity experimentally observed.