Self-assembly of the selenium-bridged novel metallacyclophanes [{(CO) 3Re(μ-SeR)2Re(CO)3}2(μ-L) 2] (1-3) has been accomplished by treating diaryl diselenide with low-valent transition-metal carbonyl and rigid bidentate azine ligands under one-pot reaction conditions. The oxidative addition of diphenyl/dibenzyl diselenides to Re2(CO)10 with 4,4′-bipyridine, trans-1,2-bis(4-pyridyl)ethylene, and 1,4-bis[2-(4-pyridyl)ethenyl]benzene afforded tetranuclear metallacyclophanes. These compounds have been characterized by elemental analysis and IR, NMR, and UV-vis absorption spectroscopic techniques. The molecular structures of metallacylophanes 1a,b and 2 were determined by single-crystal X-ray diffraction methods, and the crystal structures showed that two selenium-bridged dirhenium metallacycles were linked by two bipyridyl spacers and attained a framework of molecular rectangles. In addition, the molecular recognition capabilities of the molecular rectangles 1a,b and 2 with aromatic compounds such as pyrene and triphenylene have been investigated by studying their binding properties, using UV-visible absorption and fluorescence emission spectrophotometric methods. The nature of the binding interactions were further supported by single-crystal X-ray diffraction methods, and the crystal structures of 1b·(pyrene) and 1b·(triphenylene) revealed that CH···π interactions are mainly responsible for the binding of 1b with pyrene and triphenylene. © 2014 American Chemical Society.