The synthesis and spectral properties of novel 4-phenylacetylene-1,8-naphthalimide derivatives

A series of novel N-alkyl-1,8-naphthalimide derivatives with phenylacetylene at the C-4 position were synthesized using 4-bromo-1,8-naphthalimides and arylacetylenes as starting materials in the presence of Pd(PPh3)2Cl2/CuI under mild conditions. The absorption and fluorescence properties of these compounds were recorded and the quantum yields were measured in DMF solution using quinine sulphate as the standard. It was found that UV/vis absorption was in the range of 372-399 nm and fluorescence emission was between 428 and 531 nm. Substituent effects on absorption and fluorescence spectra are discussed.