The hydrolysis reactions of the cycloadduct IV were similar to those of its phenyl analog VI. At room temperature with concentrated sulfuric xitl, IV gave the white crystalline monoketone 2-fluoro-2-chloro-3-(cyclohex-1-enyl)-cyclobutenone (XV) and at 55-60'yellow, crystallinr. cyclohex-1-enylcyclobutadienoquinone (XVI). Since phenylcyclobutadienoquinone (I) is readily substituted in the four-membered ring by bromine to give 4-bromo-3- ...
