Inner-assembly singlet energy transfer in naphthalene–anthracene system linked by 2-ureido-4{1H}-pyrimidinone binding module

Naphthalene–naphthalene, anthracene–anthracene, and naphthalene–anthracene assemblies 1.1, 2.2, and 1.2 linked by 2-ureido-4{1H}-pyrimidinone binding module were synthesized. Fluorescence quenching and lifetime measurements demonstrate that the inner-assembly singlet energy transfer from naphthalene to anthracene in 1.2 occurs with the efficiency of ca. 89% and rate constant of ca. 9.8 × 108 s−1. Föster energy transfer mechanism operates in this energy transfer process.