Tandem Walk Rearrangement of a Protonated Dicyclopropenyl Ketone

Abstract

Upon photolysis in an organic matrix, the acyl diimide 1 was transformed into the dicyclopropenyl ketone 2. The NMR spectra of protonated 2 are temperature dependent. In the 1H-NMR spectrum, coalescence is observed, leading to a single signal for all the erl-butyl groups. The transition state of the corresponding rearrangement is probably 3.