Abstract In order to develop a chemical approach to analyze opto-electronic and biological properties of the coumarin scaffold, we focused on the synthesis library of new coumarin analogues. Starting from salicylic aldehyde derivatives, the coumarin scaffold was constructed and functionalized via selective iodination, Knoevenagel condensation and Sonogashira coupling. Our library model proposes the functionalization of three positions of the coumarin backbone. An ester or carboxylic acid at 3-position, various alkynyl moieties at 6-position and electrodonating groups (EDG) (OH, OCH3, NEt2) at 7-position were introduced. The structures of the synthesized compounds were confirmed by Nuclear Magnetic Resonance (NMR) and High-Resolution Mass Spectrometry (HRMS). Due to the abundance and low cost of terminal acetylenes, these new conjugated enyne coumarins are promising precursors with high synthetic potential, leading to the development of complex systems with a wide range of properties.
Keywords Coumarin, Sonogashira Coupling, alkynyl, electrodonating group.