The synthesis of angularly fused polyaromatic compounds by using a light-assisted, base-mediated cyclization reaction

The synthesis of substituted polyaromatic compounds that contain at least four benzene rings fused together in an angular fashion is described. Suzuki coupling of 1-bromo-3,4-dihydronaphthalene-2-carbaldehyde with a number of aromatic boronic acids affords products such as 1-(1,4-dimethoxy-3-methyl-2-naphthyl)-3,4-dihydronaphthalene-2-carbaldehyde. Exposure of these dihydronaphthalenes to potassium tert-butoxide and DMF at 80°C yields polyaromatic compounds such as 9,14-dimethoxynaphtho[1,2-a]anthracene.