Alkylnaphthalenes. IX. : Photolysis of 2-Isopropylnaphthalene

Photolysis of 2-isopropylnaphthalene (2-IPN) coated on the inner surface of a test tube and on filter paper was examined under irradiation with a high-pressure mercury lamp. The extents of degradation of 2-IPN were about 10% after 5 h, about 60% after 30 h, and approximately 100% after 96 h. Six photoproducts of 2-IPN were identified by means of gas chromatography-mass spectrometry : 2-(2-naphthyl)-2-propanol, 2-isopropenylnaphthalene, 2-acetonaphthone, β-naphthol, phthalide, and phthalic anhydride, as well as unchanged 2-IPN. The formation pathway of these photoproducts was examined by irradiation of each photoproduct under the same conditions.