Synthesis of the title compound (11) has been achieved by two routes, the cycloaddition of cyclobutadiene to tropone and addition of tetrachlorocyclopropene to an appropriate bicyclo[4.2.0]diene (6) and subsequent transformations. Acetolysis of esters of 11 afforded a rearranged allylic acetate (15) and dihydroindenylenol acetate (20). Deuterium-labeling studies indicate that 20 derives from 15 via a bicyclo[2.1.0]pentane (25) and subsequent thermal fission. Activation parameters for this process (ΔH‡ = 31.2 kcal/m ΔS‡ = -6.2 eu) are in accord with the proposed mechanism.
All Science Journal Classification (ASJC) codes
- Organic Chemistry