Intimately bound coumarin and bis(alkylaminostyryl)benzene fragments: synthesis and energy transfer

A novel trichromophoric assembly was synthesized, where two molecules of 7-alkoxy-4-methylcoumarin, acting as energy donors, were linked at a fixed distance and controlled geometry to an energy-acceptor bis(alkylaminostyryl) unit. Resonance energy transfer between the two different species was demonstrated by a careful spectroscopic analysis.