1: 92 percent / hydrogen / 5percent Pd-C / ethyl acetate 2: 77 percent / methyllithium / diethyl ether / 3 h / other tricyclic cyclopropylidene precursors, reaction regiospecificity 3: 65 percent / AgClO4 / benzene / 24 h / Ambient temperature 4: 20 mg / 2,3-dichloro-5,6-dicyanobenzoquinone / benzene / 24 h / Ambient temperature View Scheme