This paper reports the synthesis of 1,5-naphthalene-bridged bis-(benzo-15-crown-5), and its distinct fluorescent behavior derived from the self-assembly modulated by K^＋. The behavior can mimic a fluorescent "off-on-off" switch and a fluorescent "on-off-on" switch, which is similar to the dimerization and functions of enzyme to some extent.

Key words: dimerization, bis-crown ether, photoinduced electron transfer, excimer