Template-directed photochemical [2+2] cycloaddition reactions of naphthalene acrylic acid derivatives and an investigation of single-crystal-to-single-crystal transformation

Abstract

The first part of the thesis investigated the methodology study on the use of 1,8- dihydroxynaphthalene as a covalent template in the photochemical [2+2] cycloaddition reactions of naphthalene acrylic acid derivatives. This study showed that both in solution and solid state reactions, from the unsymmetrical template-bound diesters, the [2+2] cycloadducts can be formed. Importantly, the removal of the template molecule provided the products with high diastereoselectivities, whereas reactions in solution phase provided higher yields compared to solid state reactions. In the second part of the thesis, the same strategy was applied to the template-bound symmetrical diester. Photochemical [2+2] cycloaddition reactions were investigated in three different phases: (i) in powder form, (ii) as a single crystal, (iii) in solution, under 365 nm UV light. In addition to that, the effect of daylight on the cyclization of symmetrical diester was examined. For the single crystal, single-crystal-to-single-crystal (SCSC) transformation was studied. In all cases, the [2+2] cycloadduct was synthesized and isolated in good yields and with high diastereoselectivity.