The thesis concerns with the intermolecular Diels-Alder reaction of masked o-benzoquinones (MOBs) with N-phenylmaleiminde 57、2,2-dimethylcyclopentane-1,3-dione 58 and cyclopentadiene 59 to form bicycl[2.2.2]octenone compounds 61、62 and 63, then under the irradiation of a broad band of UV light wavelength centerded at 306 nm in acetonitrile, 61-63 performed sequential Norrish Type I, decarbonylation and 1,3-shift rearrangement to construct Marasmane skeleton.