Design of substituted semibullvalenes suitable for control of the cope rearrangement by two ps IR laser pulses Original Research Article

A systematic experimental search for substituted semibullvalenes yields systems which have nearly thermoneutral reactants and products (ΔH0 ≈ 0.5–1 kJ mol−1) separated by moderately low barrier (ΔE0ǂ ≈ 10–30 kJ mol−1), e.g. 2,6-dicyanoethylmethylsemibullvalene DEM-SBV (=7c⇌7c′). Theoretical model simulations suggest that their Cope rearrangement may be controlled by two infrared picosecond (IR ps) laser pulses: The first pump pulse excites the reactants to the transition state, represented by a delocalized wave packet with energy above the potential barrier. The second dump pulse stabilizes the products.