Intramolecular cycloaddition reactions of α-bromostyrene- functionalized fumaramides Shoko Yamazaki 1 , Zhichao Wang 2 , Tsumoru Morimoto 3 , Akiya Ogawa 2 1 Nara University of Education, Japan, 2 Nara Institute of Science and Technology, Japan, 3 Osaka Metropolitan University, Japan Intramolecular cycloaddition reactions of α-bromostyrene-functionalized amides of monomethyl fumarate under sustainable conditions were investigated. 1 The reaction of the amides with Et 3 N in toluene at 110 °C gave 1,4-dihydronaphthalenes. The 1,4-dihydronaphthalenes may be produced intramolecular Diels-Alder reaction, proton transfer, dehydrobromination by base along with C=C bond isomerization by proton transfer. The reaction of amide derivatives with halogen on benzene ring and alkali metal carbonates in toluene at 110 °C gave naphthalene derivatives directly. Dehydrogenation of various 1,4-dihydronaphthalenes with cesium or rubidium carbonate in toluene at 110 °C gave naphthalene derivatives. Dehydrogenation occurred without transition metals. The experimental results and DFT calculations suggest radical mechanism caused by intervention of molecular oxygen and the oxidation may be of the corresponding enolate form. Transformation of the halogen functionalized products to solvatochromic fluorescent naphthalenes has been demonstrated. Furthermore, intramolecular yclization reactions of phenypropargyl fumaramides will be shown in this presentation. References 1. Wang, Z.; Yamazaki, S.; Mikata, Y.; Oba, M.; Takashima, H.; Morimoto, T.; Ogawa, A. J. Org. Chem. 2022 , 87 , 11148-11164.
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