Synthesis of 6,11-Dihydro-11-oxodibenz[b,e]oxepin-2-acetic Acid

4-(2-Carboxybenzyloxy)phenylacetic acid (Ⅲ)was synthesized from 4-Hydroxyphenyl acetic acid(Ⅱ)and phthalide in the presence of the catalyst sodium methoxide. The molar ratio of reactants(Ⅱ ∶ phthalide ∶ sodium methoxide)was 1.0 ∶ 1.1 ∶ 2.2,the reaction time was 7 h and reaction temperature was 130℃. 6,11-Dihydro-11-oxodibenz[b,e]oxepin-2-acetic acid(Ⅰ) was synthesized from Ⅲand acetyl chloride through two-step reactions including chlorination and cyclization. The optimum reaction conditions were as follows:n(Ⅲ) ∶ n(acetyl chloride)=1 ∶ 1.25,reaction time 6 h and reaction temperature 100℃. The overall yield that was calculated from Ⅱ was 48.16%. Structure of Ⅰ was characterized by IR,1H NMR and MS.